Citation: 4A_284/2018 E. A

A.a. Die International Federation of American Football (IFAF) (Klägerin 1, Beschwerdegegnerin 1) ist ein nach französischem Recht gegründeter Verein mit Sitz in X1.________. Sie ist der internationale Verband für die Sportart American Football. USA Football, Indianapolis/USA (Klägerin 2, Beschwerdegegnerin 2), Football Canada, Ottawa/Kanada (Klägerin 3, Beschwerdegegnerin 3), die Japanese American Football Association, Tokyo/Japan (Klägerin 4, Beschwerdegegnerin 4) und die Panamanian Federation of American Football, Panama City/Panama (Klägerin 5, Beschwerdegegnerin 5) sind Nationalverbände für American Football in den jeweiligen Ländern und als solche Mitglieder der IFAF. B.________ (Kläger 6, Beschwerdegegner 6) wurde nach seiner Darstellung am Kongress vom 17. September 2016 in New York zum Präsidenten der IFAF gewählt. A.________ (Beklagter, Beschwerdeführer) war während vieler Jahre Präsident der IFAF. Er behauptet, er sei nie von seinem Amt als Präsident der IFAF zurückgetreten; vielmehr sei er am Kongress vom 17. September 2016 in Paris als solcher wiedergewählt worden. A.b. A.________ war zwischen 2000 und 2014 Präsident der Swedish American Football Federation (SAFF). Im Jahre 2006 wurde er als Präsident der IFAF gewählt und in den Jahren 2008 und 2012 für weitere Amtsperioden von jeweils vier Jahren wiedergewählt. Die letzte Amtsperiode als IFAF-Präsident sollte demnach 2016 auslaufen. Während der dritten Amtsperiode von A.________ beschloss die IFAF, die Organisation der Weltmeisterschaften 2015 an die SAFF zu vergeben, die in der Folge die Gesellschaft C.________ beauftragte, die erforderlichen Vorbereitungen hierzu in die Wege zu leiten. A.________ war damals Vorsitzender dieser Gesellschaft. Bis Ende 2014 waren die anderen Vorstandsmitglieder der IFAF nicht darüber informiert worden, dass es ernsthafte Schwierigkeiten mit der Organisation der Weltmeisterschaften in Schweden gab. Es gab Anschuldigungen, wonach von der SAFF an die C.________ bezahlte Gelder verschwunden waren. A.________ hatte den Vorstand auch nicht darüber informiert, dass er im August 2014 aufgrund eines Betrugsverdachts im Zusammenhang mit einem vorangehenden Arbeitsverhältnis in Schweden verhaftet worden war. Nachdem diese Vorkommnisse bekannt worden waren, teilte die IFAF am 18. Dezember 2014 mit, dass A.________ bis Ende Januar 2015 (krankheitsbedingt) beurlaubt sein werde. Das Projekt, die IFAF-Weltmeisterschaften in Schweden durchzuführen, wurde im Dezember 2014 aufgegeben und der Anlass fand schliesslich in Canton/Ohio (USA) statt. A.c. Am 30. Januar 2015 fand in Dallas/Texas (USA) eine IFAF-Vorstandssitzung statt. Diskutiert wurden die Auswirkungen der abgesagten Weltmeisterschaften in Schweden. A.________ nahm an der Sitzung nicht teil. Ebenfalls am 30. Januar 2015 schickte der Vorstand die folgende E-Mail an A.________: "Dear A.________, I write following the Executive Board meeting held on January 30th 2015 in Dallas where the issues relating to the cancellation of the 2015 World Championships were discussed. The Board continue[s] to have deep concerns relating to the events which led to the cancellation of the Championships and issues which have subsequently arisen. At this time, based upon the information which we currently have, the Board does not have confidence that the resumption of your leadership of IFAF is in the best interests of the Federation and the sport as a whole. We formally request that your leave of absence is extended by two weeks effective from 00.01 on February 1st 2015 during which time we would like you to provide a full and detailed description of all actions undertaken in your capacity as IFAF President relating to the Championships, both in regard to the Swedish partners and wider organizations. We have prepared a statement for the IFAF membership detailing the above which we will release on January 31st. We are keen to ensure that the actions of the IFAF Board are based upon all relevant information and ensure that the IFAF Board can act in the best interests of the IFAF membership." Am 31. Januar 2015 folgte eine weitere E-Mail des IFAF-Vorstands an A.________: "Dear A.________, I write in follow up to the email which was sent last night and your subsequent conversation with Mr D.________. Thank you for your understanding of the issues which IFAF face[s] in light of the cancellation of the 2015 World Championships in Sweden and the acceptance that there needs to be a clear plan for managing the governance of IFAF between now and the Congress scheduled for this summer. We can confirm that we agree that the first step is to extend your leave of absence from the role of President. During this time you will not act in any capacity for or on behalf of IFAF. Based on our understanding of your discussion with Mr D.________ we accept that you will be seeking to leave your role as President and that we must manage this sensitively and effectively. Having discussed this, we are in agreement that we should like a confirmation of your intention to resign your Presidency by February 7th 2015 so we can work with you to establish a clear timetable for succession. Whilst we recognize that the current issues present a challenge, we would like to ensure that our members are fully aware of the positive legacy which you leave for IFAF following your time in office. We would like to discuss how we can do this with you in the coming week. We would respectfully request that you acknowledge this email and confirm and agree with the content detailed within. If you are in disagreement with any of the above, please inform us in writing at the earliest opportunity so that we can address this. [...]" A.d. Am 3. Februar 2015 sandte A.________ die folgende E-Mail mit dem Titel "IFAF Presidency and Leave of Absence" an die Mitglieder des IFAF-Vorstands: "Dear Exbo, As per the discussion with Mr. D.________ I can confirm that I will remain on leave of absence due to health reasons until April 30th (I am on sick leave in Sweden as ordered by medical doctor so it's true). I will not act for or on behalf of IFAF during this period. At April 30th I will communicate to the members something along the lines: 'I've been on a IFAF leave of absence since mid-December for health reasons and now have decided that it is best for me to resign - due to my health issues - so IFAF leadership can move forward on the important business ahead. I look forward to continuing my legacy of contributing to IFAF's progress and future when the time and my health is right.' I will as you can see per above resign at April 30th. I would although make one recommendation for the Exbo. I think it's important that the network and contacts I have built over the years in Sportaccord, ARISF and IOC (IOC members and at the IOC Sport department) is transferred and not lost when I leave. I would therefore recommend that I attend the SportAccord meeting in late April with E.________ and F.________ to assist with the introductions and transition of my relationships with SportAccord leadership, ARISF and IOC leaders to E.________ and F.________. I will explain to these leaders that I will resign on April 30th and E.________ and F.________ will be there to see/hear it. The Sportaccord convention is held in Sochi, Russia. I recommend this since I care for IFAF and that the transition should be as smooth and positive as possible. I have due to various reasons (late cancellations by others etc.) attended the two last Sportaccord conventions (Belek Turkey last year and St Petersburg Russia the year before) alone and during those two years many things have changed. For instance is the whole Sportaccord board new since two years. IFAF was allowed to attend our first ARISF congress last year. This is also the main reasoning behind resigning at April 30th. Regarding recognizing my work over the years and hopefully positive input on IFAF I leave it up to you to decide what is the appropriate action. If you feel that we shall discuss it I can of course discuss with Mr. G.________ or whom you decide to appoint in this matter. If you have other questions in regard to how the transition can be done in the best manner I will of course help as much as I can. One point is although of importance. I have now declared my intentions to you. It shouldn't be unclear to you what will happen April 30th. But I would like to be the one who informs the member federations. I don't want the members to find out via some website or social media. The part that I'm on leave of absence can of course be communicated. But not that I'm resigning April 30th. Confidentiality is important for both parties and I trust that you all will honor this agreement. If something is unclear or you have other questions please feel free to contact me. [...]." A.e. Die von A.________ vorgeschlagene Vorgehensweise wurde am 4. Februar 2015 vom IFAF-Vorstand wie folgt genehmigt: "3. Situation with Mr. A.________ After an email exchange with Mr. A.________, the Proposal is to: - Accept Mr. A.________'s resignation effective from April 30th, 2015 - Accept continuation of Mr. A.________'s leave of absence until April 30th, 2015 - Accept that Mr. A.________ will not act for or on behalf of IFAF while on leave of absence - Accept that Mr. A.________ attends Sport Accord together with two IFAF representatives Executive Board members voted all for approval of the proposal. Mr. F.________ will send a notification to Mr. A.________ of this decision. Details regarding the transition will be discussed on a later date." Mit E-Mail vom 6. Februar 2015 bestätigte F.________ gegenüber A.________ den Entscheid des IFAF-Vorstands, den Rücktritt A.________ per 30. April 2015 anzunehmen, sowie dessen Teilnahme an der bevorstehenden Sport Accord Convention zusammen mit zwei IFAF-Vertretern. A.________ antwortete nicht auf dieses E-Mail, nahm hingegen an der Sport Accord Convention vom 19. bis 24. April 2015 teil. Zwei Mitglieder des IFAF-Vorstands, F.________ und E.________, begleiteten ihn. A.f. Am 30. April 2015 verschickte A.________ die folgende auf IFAF-Briefkopf gedruckte Erklärung: "You know that the plan was for me to resign as IFAF President by April 30. As of today, due to recent meetings and strong recommendations from top IOC officials, I am although not resigning and instead continuing as President of IFAF." Am 1. Mai 2015 verschickte A.________ die folgende Erklärung: "Due to the above very clear message from the top IOC-members I'm staying until my term ends in 2016 and I would dedicate all my time in regard to secure our IOC recognition approval, our participation in the next World Beach games, Asian games, Pan-American Games and the Tokyo 2020 Olympic Games. If someone wants to bring the IFAF presidency up on the agenda at the congress this summer it would be a congress decision. Something everyone can and would have to accept since the congress is the supreme authority. Even the key IOC people will have to accept such decision. But it is clear that I leaving now due to the demand on the majority of the Executive Board will not be seen by top IOC people as the correct way to handle issues within an International Sports Federation and it will not help IFAF. Due to my health issues I will continue to stay on medical absence until end of May as prescribed by my doctor. I hope that you all agree that IFAF are for more important than my personal issues. We do not only have our IOC objectives but also the World Championship this summer. This is not the time for internal politics, it's time to work." F.________ reagierte im Namen des IFAF-Vorstands wie folgt: "We read with interest your statement today which outlined your plans to continue in the role of IFAF President. First and foremost it is of concern that the letter contains supposed endorsements from senior figures in international sport. With this matter being at present an internal issue, it is regrettable that other people may be drawn in as a point of reference either to a particular party or a process. That does nothing for our sport and its standing. Secondly, with regard to the issue of your resignation, the process and conditions were clearly laid out in your email dated 3. helmikuuta 2015 (see below). The email makes multiple references to your resignation and this was accepted by the Executive Board. That you wish to change a prior agreement is understandable given the emotions which come when leaving a post. However, the decision has been made and accepted. A failure to honour this would see an erosion of trust which means that there could in effect, be no effective working relationship between yourself and the Board even if your request to be reappointed were to be considered. We will be releasing the statement which states that the Executive Board have accepted your resignation and complied with the requested attendance at events." Darauf folgten verschiedene weitere Nachrichten und Pressemitteilungen. A.g. Am 17. Juli 2015 wurde A.________ vor der offiziellen Eröffnung des IFAF-Kongresses daran gehindert, das für Vorstandsmitglieder reservierte Podium zu betreten. Dies führte dazu, dass einige Delegierte den Saal unter Protest verliessen. Anschliessend nahm der IFAF-Kongress seinen Lauf. Unter anderem wurde F.________ bis zum IFAF-Kongress 2016 als Interimspräsident gewählt. Gleichzeitig hielten die Delegierten, die den Saal mit A.________ verlassen hatten, in der Hotellobby ein paralleles Treffen ab; unter anderem sprach diese Versammlung A.________ weiterhin das Vertrauen als Präsident aus. Es folgte ein Machtkampf um die IFAF zwischen den beiden Gruppen. Unter anderem hielt die Gruppe um A.________ Versammlungen ab, die verschiedene Beschlüsse betreffend die Zusammensetzung des Vorstands fällten. A.h. Am 29. Februar 2016 reichte die Gruppe um A.________ beim Tribunal de Grande Instance von Bobigny, Frankreich, ein Verfahren ein zur Ungültigerklärung der Beschlüsse der IFAF vom 17. Juli 2015, der Wahl von F.________ als Interimspräsident sowie dessen für die IFAF vorgenommenen Handlungen. Mit Entscheid vom 26. Mai 2016 erklärte sich das Gericht unter Hinweis auf die in den Statuten der IFAF enthaltene Schiedsklausel zugunsten des TAS für unzuständig. Ein in der Folge von A.________ beim Tribunal Arbitral du Sport (TAS) eingereichtes Gesuch um Anordnung vorsorglicher Massnahmen wurde mit Entscheid vom 14. September 2016 abgewiesen. A.i. Am 17. September 2016 hielten beide Gruppen in Paris bzw. New York City je eigene Versammlungen ab, an denen jeweils Wahlen von Vorstandsmitgliedern durchgeführt wurden. Während die Versammlung in Paris A.________ als Präsident bestätigte, wählte die Versammlung in New York B.________ als Präsident für eine Amtsdauer von vier Jahren.