Patent Grant
10636254
The present invention relates generally to public lottery games and, more particularly, to extending the play lifetime of an instant win scratch off ticket game of chance by including a conditional prize win feature.
During the 1960s, grocery stores and gas stations handed out free game cards covered with a waxy coating that hid a possible prize. The prizes tended to be small, often worth only a penny. There were also free cards that could be compared to supermarket ads in newspapers in a manner similar to the game Bingo: If a card matched the graphic symbols in print, the consumer could win food, money, or prizes. These simple participant games evolved into what today is now referred to as instant win games, where a participant can potentially win a large sum of money playing a game of chance.
The first secure instant lottery ticket was developed in 1974 by scientist John Koza and retail promotions specialist Daniel Bower. Koza and Bower were the cofounders of Scientific Games in Las Vegas, Nev. This was the beginning of the instant lottery concept. When secure instant lottery tickets debuted in May 1974, players in Massachusetts had been buying roughly $1,000,000 worth of six-digit lotto drawing tickets every week. By the end of the first seven days of marketing instant-win cards, the state had sold $2,700,000 worth of them.
U.S. Pat. No. 4,174,857 (Koza), issued Nov. 20, 1979, provides evidence of a game ticket particularly useful as an instant win ticket. The ticket comprises at least a base sheet and a cover sheet which are adhesively joined together in a peripheral portion. Information to be concealed is placed on the surface of the base sheet which faces the cover sheet. This information is concealed by covering it with a suitable, removable material which is opaque, thus concealing the information until the opaque material is removed.
U.S. Pat. No. 4,191,376 (Goldman et al), issued Mar. 4, 1980, provides for an instant lottery ticket imprinted with lottery numbers and serial numbers that are uniquely related. Lottery numbers are covered from view until after purchase. This provides for control and distribution of winners with a high degree of security. Computerized fabrication allows for high security and low-cost production.
U.S. Pat. No. 4,299,637 (Oberdeck et al), issued Nov. 10, 1981, discloses a method for making a game ticket which has a base sheet adhesively joined together in peripheral portions of sections containing information used in the game. An opaque material is applied over the release coating to conceal information in the printed areas. The opaque material is adapted to be rubbed off when the ticket is used.
U.S. Pat. No. 4,643,454 (Ondis), issued Feb. 17, 1987 and assigned to Astro-Med Inc., provides an instant game type lottery ticket having a coating on the front side which includes a first metallic layer and an outwardly facing layer of thermally responsive chemicals, a removable opaque layer over at least a portion of the thermally responsive chemical layer, and a second metallic layer on the back side of the ticket. The metallic layers include vacuum deposited silver-colored metallized layers having protective transparent plastic films thereon. Game-playing indicia can be imprinted on the lottery ticket at the point of sale without damaging the removable opaque layer by selectively activating the thermally responsive chemicals under the removable opaque layer with a thermal printhead. The transparent plastic films allow the ticket to be thermally imprinted with a thermal printhead without damaging the printhead and the metallized layers adding opacity to the lottery ticket.
U.S. Pat. No. 8,579,693 (Bennett), issued Nov. 12, 2013, discloses a system and method for providing an additional or end of game drawing to players of a lottery game. A player participates in a lottery and subsequently submits a validation code from his ticket to a lottery ticket provider. The lottery ticket provider then applies an algorithm to the validation code to determine if the player is entered into a secondary game or end of game drawing.
Approximately 43 US states and territories currently offer a lottery with a scratch off ticket available for purchase. Scratch off tickets significantly increase lottery revenue when they are utilized. A limitation to existing scratch off ticket games is that when the grand prizes associated with a specific game or series of tickets are exhausted the sales of the remaining tickets of that specific game are terminated. With increasing grand prize amounts and quantities awarded, the Lottery risks a deficit or a significant revenue shortfall if all of the grand prizes are awarded before a “critical point” in sales has occurred.
As an example, consider a scratch off lottery game with the following specifications:
1) A print run 5,400,000 divided into 50 pools and 360,000 rolls of tickets.
2) Each pool contains 108,000 tickets divided across 7200 rolls with 15 tickets per roll.
3) Each ticket costs $20.00.
4) Five grand prize-winning tickets seeded uniformly and randomly across the 50 pools amount of $1,000,000 each.
The Grand Prize tickets “seeded” across the ticket print run should allow the game to operate for an acceptable length of time. The game rules require the game to terminate when all five grand prize tickets are claimed. Using the Grand Prize seeding methods, the probability of all five grand prize tickets being won early, while low, is still possible and will result in the game being terminated “early” before ticket sales have generated sufficient revenue, leading to poor monetary performance.
As such, there is a need for a system and method to extend the playtime of an instant win scratch off ticket game.
According to various embodiments, a system, method, and non-transitory computer-readable medium for increasing the operational lifetime of a lottery game is disclosed. The system, method, and non-transitory computer-readable medium include a game specification having rules for a primary game and a conditional secondary game. The rules include that initial winnings above a predetermined threshold in the primary game allow for entry in the secondary game for a chance to increase the initial winnings.
Various other features and advantages will be made apparent from the following detailed description and the drawings.
In order for the advantages of the invention to be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only exemplary embodiments of the invention and are not, therefore, to be considered to be limiting its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings, in which:
Generally disclosed herein is a system and method to increase the operational lifetime of a scratch off ticket instant win lottery game by incorporating a conditional secondary game function. The secondary game function permits lower tier monetary prizes to be converted to upper tier prizes (Grand Prize) using an “A Priori” probabilistic method. Effectively, this adds more grand prizes to the game which can increase the temporal “lifetime” of the instant win game. Increasing the game lifetime will effectively increase the number of tickets sold prior to the game's termination (all grand prizes have been claimed thus concluding the game) and therefore improves the gross income of the game. If eligible for a prize upgrade, the game participant can play a secondary game at an officially sponsored lottery kiosk. In the event there is a “No Win” outcome on the secondary game play, the game participant keeps the original monetary prize awarded by the scratch off ticket and the player enters an extended playoff round supported by a leaderboard tracking system (if available).
Depending on hidden indicia found on the scratch off ticket 19, the following options are available to the player 20 and the game ends for the player 20:
1) There is no winner amount. There is no further action required by the player 20.
2) The player 20 has won a monetary prize below a specific threshold (the state lottery commission sets this threshold) and is able to “cash in” the scratch off ticket 19 at a lottery retailer 4, 5, 6.
3) The player 20 has won a monetary prize above the specific threshold. The player 20 can mail in a claim form with their winning ticket 19 to the lottery office 2 to receive the monetary prize or directly visit the lottery office 2 and “cash in” a winning scratch off ticket 19.
Three game participants 16A-B, 17, 18 are shown interacting with the lottery system supporting the scratch off ticket instant win game with the secondary game feature. Player 18 has just purchased an instant win scratch off ticket 15 with the new secondary game feature from an authorized lottery retailer 6. Player 18 has revealed the indicia hidden on the scratch off ticket 15 by rubbing off the removable coating on the scratch off ticket 15. Player 18 has concluded that he has no winnings. To confirm that conclusion, player 18 can return to the authorized lottery retailer 6 and have them confirm the outcome by using an optical scanner to read the ticket information. The ticket information is communicated from the authorized lottery retailer 6 to the main lottery office 2 via a secure network 7 to confirm via the game database (not shown) in the lottery office 2 that the player 18 ticket is not a winner.
Player 17 has made a purchase of a scratch off ticket 14 from an authorized lottery retailer 5. After revealing the ticket 14 indicia by rubbing off the top coating on the ticket 14, player 17 has determined the scratch off ticket 14 represents a small win of $20. According to example game rules (described later with regards to
Player 16A purchases a scratch off lottery ticket 13 from an authorized lottery retailer 4. After exposing the indicia on the purchased scratch off ticket 13, player 16A identifies that they are a $10,000 winner. According to the example rules of the game, the $10,000 prize is above the threshold allowing player 16A to take advantage of the secondary game monetary upgrade. To determine if the ticket 13 will be upgraded to a million-dollar win, player 16A must visit the lottery office 2 and play the electronic kiosk 8 providing a secondary game win opportunity. Player 16A inputs his or her personal details and optically scans the scratch off ticket at the kiosk 8. Once the player's 16A information, which includes information from the scratch off ticket 13, is loaded into and confirmed by the game database (not shown), player 16A may try their luck at the kiosk 8. The kiosk 8 indicates player 16A has just upgraded their winnings to $1,000,000 and leaves with their winnings becoming a million-dollar winner 16B.
The game file specifications 1 are shown as a building separate from the main lottery office 2. However, the building only represents a “placeholder” for development, where a secure computer system (physically and electronically secure) establish the specifications 1. This secure computer system is independent of the main lottery computer system associated with the lottery office 2. The main lottery computer system may reside at a “server farm”, which constitutes a large number of computers (example 100 or more) that includes extensive internet secure communications. The main lottery computer system is designed to communicate with the at least thousands of lottery retail outlets (shown as examples 4, 5, 6). The main lottery computer system may also contain one or more computers which support large disk arrays and provides database functionality.
The secondary game kiosk 8 is shown in
A printing computer located at a printing facility 3, which is separate from the specification computer system for the game specifications 1, identifies the unique contents for every single ticket being printed. For example, if there were 5,400,000 tickets being printed, there would be 5,400,000 records in the file. The ticket printing facility 3 should be both electronically and physically secure.
Step 200 starts the process. At step 201 the player purchases a scratch off ticket at a retail lottery store of their choice. In step 202 the player scratches off the ticket coating to reveal the underlying indicia. At step 203 the player examines the ticket to determine if there is any win combination. If there is no win combination, the play event is complete and therefore exit 204 occurs. Purchasing another ticket is the only option to “stay in the game”.
If at step 203 the player determines they have a winner, the player needs to determine (according to the rules of the game which may state by example a specially marked ticket with a unique symbol or that a certain prize tier must be shown) if the win entitles them to a secondary game upgrade attempt, which occurs at step 205.
If the ticket is not eligible for a secondary game upgrade, at step 208, the player now has to determine if the ticket face value allows for payment at any lottery retailer or if the win amount is above a specific threshold set by the lottery commission (stated in the rules of the game). If the win amount is over the preset threshold, the player will have to mail in the scratch off ticket 213 or visit the main lottery office in order to redeem their winnings. The lottery database is updated at step 216, the lottery will issue a check for the winning amount at step 218, and the event is complete at step 221. If ticket prize value is below the threshold of local reimbursement, the player proceeds to an authorized lottery retailer to collect their winnings 209. The lottery retailer will inform the lottery office of the player's win status, where in turn the game database at the lottery office is updated with the player's win information 210. The player can then receive their winnings from the retailer in exchange for the winning ticket 214 and leave the retailer with their winnings, completing this event 215.
In the event the player's ticket winnings are eligible for enhancement by playing the secondary game feature, the player will have to travel 206 to the nearest secondary game kiosk, which for this example exists at the lottery office. Once at the lottery office, the player will provide their personal information to update the game database 207. The player will then proceed to play the secondary game 211 on the game kiosk. The win determination function (to be described in further detail with respect to
For the sample game that players, such as players 16A-B, 17, and 18, are participating in,
Prior to printing however, the tokenNum variable is checked 69. If tokenNum equals zero, the ticket is a non-winning ticket and the process can go directly to the printing process. If the value is greater than zero the ticket should be a winner so the method must modify the YourNumArray( ) so one element matches an element in the WinningNumArray.
The method will first copy the text string for the winning prize from PrizeStrArray(tokenNum) to a temporary variable WinningPrize 70. The method will interface with a true random number generator (RNG) to select which index in the WinningNumArray( ) will be used as the matching numbers and will copy to a temporary variable called WinningNum 71. The method will next interface again to the RNG to determine which location in the YourNumArray will contain the matching number and will assign that to the WinningLocation variable 72. The method then replaces the number at the index YourNumArray(WinningLocation) with the number stored in the WinningNum variable 73. The program will also replace the text stored at WinningPrizesArray(WinningLocation) with the WinningPrize variable 74.
The various arrays associated with the Winning Numbers and Your Numbers area are now properly populated and the scratch off ticket can now be printed through a specialized printing process which will be known by those skilled in the art 75. Once the specialized printing process is completed, the indexPtr variable is incremented by one 75 and checked to see if it is equal to 108,000 at step 77. If IndexPtr is less than 108K, the module copies return to the step of reading the next TokenNum 63. If IndexPtr equals 108K, then all tickets in that prize pool have been printed and the variable PoolCount is incremented by one 78. The method then compares the PoolCount to 50 at step 79 to check if there are more prize pools left. If there are, control of the module returns to setting the IndexPtr to zero 61. If all 5,400,000 scratch off tickets have been printed, the method ends 80.
In Swap 2 at step 96 the result of the R (random number) mod Pointer (“array_pointer”) is zero. Therefore, the values in the array at locations zero and four are transposed. Swap 3 at step 97 has R mod Pointer equal to one so the value “1” stored at array location one is transposed with “3” which is stored at array location three. Swap 4 at step 98 again has R mod Array_Pointer (now equal to two) equal to one. The two values at the array locations one and two have already been swapped by previous loops but are once again transposed to new locations. The routine continues through one more loop as Swap 5 at step 99. Once the values are transposed in swap 5, the function will decrement the shuffle_count and determine there are no more swaps to occur and will return to the calling function with the final contents 100 of the array being 5,4, 3, 1, 0, 2.
If left at an unsigned 32-bit integer, the random values would vary from 0 to 4,294,967,296.
When targeting specific probabilities, a modulus function is used to set the upper limit on the random outcome, by example 1 in 100. A modulus of 100 applied to the 32-bit raw random number value will produce a random value of 0-99. The modulus function is based on an arithmetic decision function generally expressed as: N/D, remainder R. By example, if N is 10 and D is 8, then R=2. For the purpose of random number generation, the modulus function introduces “truncation bias” which will affect the statistical outcome. The effect of truncation bias must be compensated for when producing random integer value between 0 and “N”.
Step 103, 104 starts the function of generating a 32-bit unsigned random number between a value of 0 to “N”, where N is an input variable defining the upper limit of the random number return. Step 105 determines an “ANDing” logical mask to be applied to the modulus “N” to correct for truncation bias (
Step 110 determines if the random number exceeds the modulus limit defined by the bit mask. If the random number is within the limits of the bit mask, the value is returned at step 113. If the random number exceeds the bit mask limit, the loop count is incremented at step 111 and the loop_count limit is checked (64 in the example). If loop_count is 64 at step 112, then an error is declared at step 114, otherwise a new random number is selected, returning to step 108.
How and which prize a player wins is defined next in the rules. There is a table included in the rules that shows in more detail the prizes available to win, the odds of winning each prize and the number of tickets printed that will contain each of the prizes.
There should be a section in the rules which describe various aspects of the conditional secondary game drawing such as the eligibility to enter the secondary game and how the player would participate in the game. Also indicated is the maximum number of conditional secondary game winners (10). There is also a table which shows which prizes can be won in the conditional secondary game dependent on the original amount won on the scratch off ticket. In this example the player has a chance to win $1,000,000 if their original scratch off ticket was a winner for the amounts of $1000, $10000 or $100000. The table also indicates that odds of winning the secondary game based on the original win amount.
Some lotteries may offer retailer incentive awards and bonuses for selling lottery tickets specifically winning lottery tickets. If so, the details of these awards and bonuses will be described in the game rules. There is also a disclaimer indicating the time frame to redeem a winning scratch off ticket, which laws will be in effect for this game (which is typically the state where the lottery office is located), and how the player may redeem their winning scratch off tickets.
There is a disclaimer that the lottery office may announce a termination date which would end the sale of this games scratch off tickets. A termination date may be announced for several reasons such as a predetermined date or all top prize tickets have been redeemed.
There are multiple scratch-to-reveal areas on this scratch off ticket 153, 154, 156 which are shown in their initial state (unrevealed). In this example, scratch-to-reveal area “winning numbers” 153 contains the numbers that must be matched in the “your numbers” area 154 for the player to win prizes. Area 155 of the scratch off ticket 150 gives the player a brief description of how to win prizes. If any number revealed in “winning numbers” area 153 are revealed in the “your numbers” area 154, the player will win the amount shown under the matching number.
A control number 157 which typically indicates the ticket position on a roll of tickets is shown in the lower left corner of the ticket. In this example the control number 157 indicates the ticket was the twelfth ticket on the roll. The “scratch to cash” area 156 is another scratch-to-reveal area. When revealed, this area 156 typically displays a type of bar code used to electronically scan the ticket and to verify if the scratch off ticket 100 is a winning or non-winning ticket as stored in the lottery authority's central database.
A quick response (QR) code 158 is revealed in the “scratch to cash” area 156 in the lower right corner of the scratch off ticket. This code can be electronically scanned with an optical scanner at an authorized lottery retailer and/or at the secondary game kiosk to confirm the ticket is valid and has not been previously redeemed.
The disclosure of a ticket sales maximization method and system using a secondary game constitutes the improvement over the prior art instant win scratch off ticket games.
There are at least two fundamental variants (embodiments) of the secondary games that may be deployed. Both embodiments are designed to increase the number of grand prize tickets by upgrading lower tier monetary prizes to a grand prize value conditionally, using an a priori method with true random number generators.
The first variant for the secondary game feature uses a Bernoulli Trial to produce a win or no-win outcome.
The second variant of the secondary game produces a score for the player using, by example, dual spinning wheels whereby, the stop positions of the wheels are combined algebraically. By example, two wheels are implemented in a video format using a computer application program to execute the procedures required. Both wheel one and wheel two have 32 slots labeled 0 through 31. The formula used to generate a random number between 0 and 1023 is:
X=(32×N)+M
While this example uses a linear equation, it is not intended to be a limitation for the invention. Other formulations can be used such as exponential, quadratic, etc.
The variable “X” represents the final random value. The variable “N” represents the slot position on wheel one (0-31). Variable “M” represents the slot position of wheel two (0-31). A true random number generator with a modulus of 32 is used to generate the values “M” and “N”. The software application will render the video image to simulate wheel movement and have the wheels “stop” at a final location based on the random values of “N” and “M”.
The “scoring” feature of the second embodiment of the secondary game feature permits further flexibility when providing for multitier winner upgrades. Number ranges such as “0-50” to upgrade a $1,000 win or “51-70” to upgrade a $5,000 win can be implemented with this method. Also, for tertiary competitions, such as no-category (range 500-1023 upgrade by example), can be used as a final playoff and prize upgrade option.
By policy, the secondary win upgrade feature may guarantee one or more players will have their monetary winnings value transformed into a grand prize. However, it is possible that the secondary game methods described herein may not produce an upgraded winner based on the probabilistic nature of the secondary game process. As such, a further system element and method may be added using a leaderboard to keep track of players that failed to receive an upgrade to their scratch off winnings. After all the potentially upgradable tickets have become sold and/or played, a determination is made to identify any upgrade winners. If none are found, then the players placed in the leaderboard may replay the secondary game on a FIFO (first in, first out) basis.
The computer system 170 contains a central processing unit, hard disk drive, and sufficient random-access memory (RAM). The software operating system may be a Microsoft version of Windows, Linux or Unix, or a suitable software system applicable to the kiosk 8. A custom application program 175 will interact with the various physical elements of the kiosk 8 (as seen below). The kiosk 8 may maintain a local database 173 to record transactions for secondary game play events.
Part of the kiosk 8 is a screen 171, such as an LCD screen, which serves multiple kiosk 8 functions such as player information entry or allowing a player to participate in the secondary game opportunity. In
The optical scanner 172 is used to read critical information found printed on the player's scratch off ticket. The ticket information may be stored in the kiosk 8 local database 173 as well as confirmed and stored in the lottery office 2. The ticket information is verified from the ticket information used in the initial printing process at the ticket printing facility 3.
A printer 174 is used to provide a receipt for the game player indicating that they had played the secondary game. The receipt will include the time and date the secondary game was played, as well as key ticket information and the outcome of the secondary game once played.
The mouse 176 and keyboard 178 are standard input devices for the kiosk 8 that permit player information to be logged into the kiosk 8 prior to the player playing the secondary game. The mouse 176 and the keyboard 178 are also required when an authorized technician is performing maintenance on the kiosk 8. It should be noted that the mouse/keyboard functionality can also be incorporated into the screen 171 as a touchscreen.
The momentary push button 180 is connected to the kiosk 8 using a standard interface such as USB. The player will press the button to activate the play sequence of the secondary game. This can also be implemented in the screen 171 as a touchscreen.
The internet connection 179 is used to communicate with the lottery office computers (not shown).
The secondary game enhancement uses an entropy source (such as random number generator 177) to determine if a player's winning amount will be upgraded to a higher value.
The application program 175 is the custom software to implement the secondary game, as well as manage local database 173 information and communicate with the lottery office 2 using the internet portal 179.
It should be understood that the kiosk 8 in the example system is located in the lottery office 2. However, this is by example only, in that multiple kiosks 8 can be supported. By example, every authorized lottery outlet 4, 5, 6 may have a secondary game kiosk 8 at their physical location, or a secondary game kiosk 8 could be at any other alternative location. In the event that multiple kiosks 8 are deployed throughout the system, each kiosk 8 will have a unique electronic identifier.
The function is entered at step 230. Step 231 determines the probability coefficient for a win based on a stored table as shown by example in
In another embodiment, the game player has the opportunity to upgrade their base prize to one of several prizes of a higher value. While a video solution for this embodiment is shown, it should not be considered a limiting factor. The kiosk system utilized in this embodiment includes all components previously described with the exception that the app 175 would be a custom implementation. The app 175 would contain a control table (described below with respect to
Referring back to
Referring again to
This is due to the fact that ticket sales are still active. Typically, players have up to one year after the end of ticket sales to claim any prizes won on the scratch ticket and thus claim the chance to play the secondary game. The sample leaderboard shows the top five “non-winning” scores achieved on the secondary game. To provide privacy to the player but to still allow them to follow their standings in the leaderboard, the players first name and last initial and their resident city is shown 313. A unique identifier would be the ticket control number 314 of the scratch off ticket which was read by the optical scanner of the secondary game kiosk. Finally, displayed for each player would be their score achieved in the secondary game 315. If the minimum number of prizes haven't been awarded when the last date to claim prizes has passed, the lottery will issue the grand prize amount to the top player. If there are more than one player with the top score, the lottery may opt for a spin off event until only one player has a top score. The lottery may also issue each player the top prize or divide the top prize equally between the players.
As such, generally disclosed herein is a system and method to increase the operational lifetime of a scratch off ticket instant win lottery game by incorporating a conditional secondary game function. The secondary game function permits lower tier monetary prizes to be converted to upper tier prizes (Grand Prize) using an “A Priori” probabilistic method. Effectively, this adds more grand prizes to the game which can increase the temporal “lifetime” of the instant win game. Increasing the game lifetime will effectively increase the number of tickets sold prior to the game's termination (all grand prizes have been claimed thus concluding the game) and therefore improves the gross income of the game. If eligible for a prize upgrade, the game participant can play a secondary game at an officially sponsored lottery kiosk. In the event there is a “No Win” outcome on the secondary game play, the game participant keeps the original monetary prize awarded by the scratch off ticket and the player enters an extended playoff round supported by a leaderboard tracking system (if available).
It is understood that the above-described embodiments are only illustrative of the application of the principles of the present invention. The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. Thus, while the present invention has been fully described above with particularity and detail in connection with what is presently deemed to be the most practical and preferred embodiment of the invention, it will be apparent to those of ordinary skill in the art that numerous modifications may be made without departing from the principles and concepts of the invention as set forth in the claims.
This application claims priority to provisional application 62/919,389, filed Mar. 11, 2019, which is herein incorporated by reference in its entirety.
| Number | Name | Date | Kind |
|---|---|---|---|
| 4174857 | Koza | Nov 1979 | A |
| 4191376 | Goldman et al. | Mar 1980 | A |
| 4299637 | Oberdeck et al. | Nov 1981 | A |
| 4643454 | Ondis | Feb 1987 | A |
| 8579693 | Bennett et al. | Nov 2013 | B2 |
| 20010044336 | Reiss | Nov 2001 | A1 |
| 20030116916 | Cherry | Jun 2003 | A1 |
| 20040056416 | Bennett, III | Mar 2004 | A1 |
| 20070057461 | Meyer | Mar 2007 | A1 |
| 20080045299 | Bennett, III | Feb 2008 | A1 |
| 20090061992 | Boykin | Mar 2009 | A1 |
| 20090186680 | Napolitano | Jul 2009 | A1 |
| 20120136465 | Guinn | May 2012 | A1 |
| 20150310696 | Mound | Oct 2015 | A1 |
| 20170024954 | Chhabra | Jan 2017 | A1 |
| 20180012453 | Anderson | Jan 2018 | A1 |
| 20180068529 | Delekta | Mar 2018 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 62919389 | Mar 2019 | US |
