Batman Group (hereinafter BG) in order to report on issues of authorship linked to the relationship that has united us with the development team 4Mhz and especially with its programmer Javier García Navarro (hereinafter JGN), we communicate that:

1) BG has maintained a close relationship with JGN since the foundation of 4Mhz, providing selflessly original Rhino's routines for 4Mhz games.

2) All the routines that BG has contributed to 4Mhz were developed by Rhino by express request and tailored to the needs of JGN, among which are included:

    * Split Screen used in the games Adiós a la Casta 1 and 2, Cuauhtémoc and Profanation 2.
    * Vertical hardware scroll.
    * Horizontal hardware scroll, including the engine and the complete source code of our Mario demo that is currently used as basis in the development of the next 4Mhz game, Lady Phoenix.

3) BG has not asked JGN for any kind of compensation for these codes, being completely disinterested contributions and trusting fully in the good use and honesty of JGN.

4) As a result of our full trust in JGN, BG had not tracked how our contributions were mentioned on his game credits, authorship files and statements in the media.

5) We recently discovered the following facts:

5.1) In the special videos of CPCRetroDev 2017 and 2018 of the Youtube channel "Juanje Juega" a false information was spread. The authorship of the Rhino's Split Screen routine is attributed to JGN in the following way:

    * Special CPCRetroDev 2017 (1:18:30) – To Fran Gallego's comment "it would be good for students if you tell them how you did the Split Screen", JGN responds as if he had done it, without mentioning at any time that the author is Rhino, attributing it to himself by omission.

    * Special CPCRetroDev 2018 (3:45:30) - To Fran Gallego's comment that Jarlac has a part of JGN in reference to Rhino's Split Screen routine, JGN is again attributed authorship without ever mentioning the real author and also attributing to itself the "good practice" and "generosity" of providing "his" code as the basis for Jarlac's Split Screen.

5.2) In the Profanation 2 authorship file presented by 4Mhz at CPCRetroDev 2017, Rhino's authorship of the Split Screen code used in the game does not appear anywhere. It is also not mentioned in the game credits or in any other 4Mhz game, except Adiós a la Casta 1.

5.3) In Jarlac's authorship file presented by Retrobytes at CPCRetroDev 2018, as a result of JGN's repeated appropriation of our code, Retrobytes attributes to JGN the authorship of the code that served as the basis for Jarlac's Split Screen.

6) After verifying that the Split Screen code used in the 4Mhz games mentioned above is the one originally provided by Rhino, without having any kind of modification or change that could justify the statements that JGN makes by action or omission about his authorship, BG decides to contact JGN to fix the issue.

7) On December 14th there is a first call from Rhino to JGN, where it is proposed and JGN agrees to settle the matter amicably by publishing a announcement with the sole purpose of clarifying that the author of the Split Screen routine used in the 4Mhz games is Rhino and not JGN as had been manifested in the aforementioned media.

8) As a consequence of this agreement, 4Mhz publishes a tweet in which it thanks the "help in the Split Screen routine". BG understands that this tweet does not serve the purpose of making Rhino's authorship clear, since helping to do something does not imply the authorship and this would continue to be attributed to JGN and, in any case, the tweet is not true, since Rhino has not helped to do the routine, but is the author of the routine in its totality. Tweet

9) There is a second call from Rhino to JGN to say that the tweet does not comply with what was agreed and both parties agree to make a joint announcement to definitively settle the matter of authorship in the coming days.

10) On 12/16/2018 JGN informs us that 4Mhz is not going to publish any joint announcement as we had agreed, without making any proposal regarding its content.

11) From BG we regret the impossibility of reaching a friendly solution with JGN despite all our efforts, definitely seeing the trust we had placed in him shattered, so we are forced to take the following action:

From today, we break our relationship with 4Mhz and we disauthorize all use of our code in their games, including any part that could be used in their project currently in development, Lady Phoenix.

12) In spite of the enormous sadness and disappointment that these facts produce to us, we are conscious that it is an isolated case and that in the scene prevails the spirit of collaboration and respect to the authorship, reason why our disposition to collaborate with anyone who asks for our help remains intact, as we have always done since BG.