Cookies on the Gambling Commission website

The Gambling Commission website uses cookies to make the site work better for you. Some of these cookies are essential to how the site functions and others are optional. Optional cookies help us remember your settings, measure your use of the site and personalise how we communicate with you. Any data collected is anonymised and we do not set optional cookies unless you consent.

Set cookie preferences

You've accepted all cookies. You can change your cookie settings at any time.

Skip to main content
  1. Home
  2. Licensing authorities

Guidance

Guidance to licensing authorities

The Gambling Commission's guidance for licensing authorities.

Published
1 April 2021

Last updated
7 May 2024 - Changes

Document actions
Print or save (opens in new tab)

Contents

RTS 7 – Generation of random outcomes

Applies to:

Gaming (including bingo), lotteries, and betting on virtual events

RTS aim 7

To ensure that games and other virtual events operate fairly.

RTS requirement 7A

Random number generation and game results must be ‘acceptably random’. Acceptably random here means that it is possible to demonstrate to a high degree of confidence that the output of the RNG, game, lottery and virtual event outcomes are random through, for example, statistical analysis using generally accepted tests and methods of analysis. Adaptive behaviour (that is, a compensated game) is not permitted.

Where lotteries use the outcome of other events external to the lottery, to determine the result of the lottery the outcome must be unpredictable and externally verifiable.

RTS implementation guidance 7A

  1. RNGs should be capable of demonstrating the following qualities:
    1. the output from the RNG is uniformly distributed over the entire output range and game, lottery, or virtual event outcomes are distributed in accordance with the expected or theoretical probabilities
    2. the output of the RNG, game, lottery, and virtual event outcomes should be unpredictable, for example, for a software RNG it should be computationally infeasible to predict what the next number will be without complete knowledge of the algorithm and seed value
    3. random number generation does not reproduce the same output stream (cycle), and that two instances of a RNG do not produce the same stream as each other (synchronise)
    4. any forms of seeding and re-seeding used do not introduce predictability
    5. any scaling applied to the output of the random number generator maintains the qualities as detailed
  2. For lotteries using external events - where it is not practical to demonstrate 7A the events outcomes should be:
    1. unpredictable, that is, events should be selected only where they may reasonably be assumed to be random events
    2. unable to be influenced by the lottery operator (or external lottery manager)
    3. publicly available and externally verifiable, for example, events that are published in local or national press would be acceptable.
  3. For games or virtual events that use the laws of physics to generate the outcome of the game (mechanical RNGs), the mechanical RNG used should be capable of meeting the requirements in a. where applicable and in addition:
    1. the mechanical pieces should be constructed of materials to prevent decomposition of any component over time (for example, a ball shall not disintegrate)
    2. the properties of physical items used to choose the selection should not be altered
    3. players should not have the ability to interact with, come into physical contact with, or manipulate the mechanics of the game
  4. Restricting adaptive behaviour prohibits automatic or manual interventions that change the probabilities of game outcomes occurring during play. Restricting adaptive behaviour is not intended to prevent games from offering bonus or special features that implement a different set of rules, if they are based on the occurrence of random events.

RTS requirement 7B

As far as is reasonably possible, games and events must be implemented fairly and in accordance with the rules and prevailing payouts, where applicable, as they are described to the customer.

RTS implementation guidance 7B

  1. Games should implement the rules as described in the rules available to the customer before play commenced.
  2. The mapping of the random inputs to game outcomes should be in accordance with prevailing probabilities, pay tables, etc.
  3. When random numbers, scaled or otherwise, are received, for example, following a game requesting a sequence of random numbers, they are to be used in the order in which they are received and they may not be discarded due to adaptive behaviour.
  4. Numbers or sequences of numbers are not to be discarded, unless they fall outside the expected range of numbers required by the virtual event – such an occurrence should result in an error being logged and investigated.

RTS requirement 7C

Game designs or features that may reasonably be expected to mislead the customer about the likelihood of particular results occurring are not permitted, including substituting losing events with near-miss losing events and simulations of real devices that do not simulate the real probabilities of the device.

RTS implementation guidance 7C

  1. Where a virtual event simulates a physical device, the theoretical game probabilities should match the probabilities of the real device (for example, the probability of a coin landing heads must be 0.5 every time the coin is tossed).
  2. Where multiple physical devices are simulated the probabilities of each outcome should be independent of the other simulated devices.
  3. Games may not falsely display near-miss results, that is, the event may not substitute one losing outcome with a different losing outcome.
  4. Where the event requires a pre-determined layout (for example, hidden prizes on a map), the locations of the winning spots should not change during play, except as provided for in the rules of the game.
  5. Where games involve an element of skill, every outcome described in the virtual event rules or artwork should be possible, that is, the customer should have some chance of achieving an advertised outcome regardless of skill.
  6. Where a customer contributes to a jackpot pool, that customer should be eligible to win the jackpot whilst they are playing that game, in accordance with the game and jackpot rules.

RTS requirement 7D

The rules, payouts and outcome probabilities of a virtual event or game may not be changed while it is available for gambling, except as provided for in the rules of the game, lottery or virtual event. Such changes must be brought to customer’s attention.

RTS implementation guidance 7D

  1. Changes to game or event rules, paytables or other parameters that change the way in which a game, lottery, or event works, the winnings paid, or likelihood of winning (except as described in 7Dc), should be conducted with the game or event taken offline or suspended.
  2. Altered games, lotteries, and events should display a notice that informs customers that the game or event has been changed, for example, ‘rules changed’, ’new odds’, or 'different payouts’. The notice should be displayed on game selection screens and on the events themselves if it is possible for the customer to go straight to the event without using a selection screen.
  3. This requirement is not intended to prevent games and virtual events where specified changes occur legitimately, in accordance with the game or event rules, for example:
    1. virtual events, such as virtual racing products where the odds differ from event to event depending on the virtual runners
    2. virtual games, such as bingo where the odds of winning are dependent on the number of entrants
    3. games with progressive jackpots, where the amount that can be won changes over time
    4. games with bonus rounds where different rules apply, so long as these rounds are properly described to the customer
    5. unspecified changes to rules, paytables or other parameters that change the way in which a game, lottery or event works are not permitted, for example, rules that state ‘game rules may be changed at any time’ would not be acceptable.

RTS requirement 7E

Except in the case of subscription lotteries, the system clearly and accurately display the result of the game or event and the customer’s gamble. The result must be displayed for a length of time that may reasonably be expected to be sufficient for the customer to understand the result of the game or event in the context of their gamble.

RTS implementation guidance 7E

The game artwork and text should be sufficient to provide the customer with all of the information required to determine whether they have lost or won, and the value of any winnings.

Is this page useful?
Back to top