At a glance
RSF Firm in 30 seconds
RSF Firm is the name by which the press has identified a Real Sociedad ultra group since at least 2019; El Español described it in 2022 as the continuation of the «legendary Peña Mujika». El Imparcial (January 2025) and Estoesatleti (April 2026) attribute to it an abertzale and far-left orientation. Its name appears in the 2019 call for a march in support of ETA prisoners and in the attack suffered by Real Sociedad fans in Rome in January 2025, where, according to Cadena SER, «many» of those attacked belonged to the group, «but not all». The press last cited it in April 2026, in Seville, before the Copa final.
- Club
- Real Sociedad
- City
- San Sebastián
- Stadium
- Reale Arena
- Situation
- Cited by the press in Seville before the Copa final, after the removal of some 150 fans (April 2026)
Documented history
RSF Firm: Real Sociedad's ultra group, according to the press
RSF Firm is the name by which the press identifies a Real Sociedad ultra group. In January 2022, El Español linked it to the «legendary Peña Mujika (now with RSF Firm)». No source found dates its founding or explains the change of name.
Background: the Peña Mujika
On 22 January 2022, El Español described Real Sociedad as having «the legendary Peña Mujika (now with RSF Firm)» and noted that the radicals of several northern clubs share the abertzale leaning. The source does not specify when or how the change of name took place.
See this section's source ↗2019: the call for the prisoners
In December 2019, according to El Independiente, representatives of Indar Gorri, Real Sociedad Firm, Iraultza 1921, Indar Armagiña and Herri Norte called a march in support of ETA prisoners in Mont-de-Marsan under the slogan «On the road to amnesty». The prisoners themselves rejected it.
See this section's source ↗2023: Roma and Benfica at Anoeta
On 16 March 2023, Football Italia published a video of the attack on a bus of Roma supporters before the Europa League match at Anoeta and reported that Italian and Spanish accounts attributed it to RSF Firm. On 9 November, Monesport stated that members of the group had taken part in the fight with Benfica ultras before the match. These are press attributions; no court ruling on these events has been found.
See this section's source ↗January 2025: the attack in Rome
According to Naiz, more than 80 Lazio ultras attacked on the night of 22 January 2025 Real Sociedad fans whom the Italian press identified as members of «RS Firm»; nine were injured, three of them by knife. Radio San Sebastián specified on 25 January that «many belonged to the RSF Firm group, but not all». El Imparcial described the group as «identified with abertzale and far-left positions» and the attackers as far-right.
See this section's source ↗April 2026: Seville
On 18 April 2026, the Policía Nacional identified and removed some 150 Real Sociedad fans in Seville before the Copa del Rey final. Estoesatleti, an Atlético-leaning outlet citing the police and Diario de Sevilla, described RSF Firm as a group «of far-left and abertzale ideology», on good terms with the Biris of Sevilla and with Bultzada, and said the police had spotted some of its members.
See this section's source ↗Key dates
Timeline of RSF Firm
2019 · Call for the prisoners
In December, «Real Sociedad Firm» is among the groups calling a march to Mont-de-Marsan, according to El Independiente.
2022 · Reference to the Peña Mujika
On 22 January, El Español speaks of the «legendary Peña Mujika (now with RSF Firm)».
2023 · Roma and Benfica at Anoeta
The press attributes to it the attack on a Roma bus (March) and the fight with Benfica ultras (November).
2025 · Attack in Rome
On 22 January, Lazio ultras attack Real Sociedad fans; Radio San Sebastián says many were from RSF Firm, «but not all».
2026 · Copa final in Seville
On 18 April, the Policía Nacional identifies and removes some 150 fans; Estoesatleti cites RSF Firm.
Ideology and identity · RSF Firm
The press attributes to RSF Firm an abertzale and far-left orientation. El Imparcial described it on 23 January 2025 as «identified with abertzale and far-left positions», and Estoesatleti, on 18 April 2026, as «of far-left and abertzale ideology». In January 2022, El Español attributed «their abertzale leaning» to the radicals of Real Sociedad, Athletic, Osasuna and Alavés. In December 2019, El Independiente placed «Real Sociedad Firm» among the groups that called a march in support of ETA prisoners, rejected by the prisoners themselves. These are press attributions; no statement of its own by the group defining its ideology has been found.
Source of this description ↗Frequently asked questions
Getting to know RSF Firm
What is RSF Firm?
It is the name by which the press identifies a Real Sociedad ultra group, which El Español linked in 2022 to the «legendary Peña Mujika».
What is RSF Firm's ideology?
The press attributes to it an abertzale and far-left orientation (El Imparcial, January 2025; Estoesatleti, April 2026). No statement of its own by the group has been found.
What is its relationship with the Peña Mujika?
El Español described it in 2022 as «the legendary Peña Mujika (now with RSF Firm)». No source found explains the transition.
Were all those attacked in Rome from RSF Firm?
No. According to Radio San Sebastián (25 January 2025), «many» belonged to the group, «but not all».
Who are RSF Firm's rivals?
The press documents clashes with Lazio ultras (Rome, January 2025) and, according to Monesport, with Benfica ultras (Anoeta, November 2023). Estoesatleti speaks of a historic rivalry between the Real and Atlético supporters.
Who are RSF Firm's friends?
Estoesatleti (April 2026) cites good relations with the Biris of Sevilla and with Bultzada. In 2019 its name appeared alongside Indar Gorri, Iraultza 1921, Indar Armagiña and Herri Norte in a joint call.
Where does RSF Firm stand in the stadium?
No source found places the group in any particular section of Anoeta or the Reale Arena.
Is RSF Firm still active?
The press cited it in April 2026, on the occasion of the presence of Real Sociedad fans in Seville before the Copa final.
When was RSF Firm founded?
No source found dates its founding. Its name has appeared in the press since 2019.
What does the name RSF Firm mean?
It is not recorded. No source found explains the name.
Sources
The documents behind this history
Each source keeps its date and scope. Titles appear in their original language. An insider account, an announcement and an official decision document different facts.
- Los ultras más violentos de La Liga siguen ahí aunque no los veamos: peleas en la calle y dinero negro ↗
El Español · 22 January 2022
Reference to the Peña Mujika and RSF Firm; abertzale leaning of the northern radicals.
- "Le asestaron trece puñaladas": el relato de la noche de terror de los aficionados de la Real en Roma ↗
Radio San Sebastián · Cadena SER · 25 January 2025
Distinguishes group members from other travellers in the Rome attack.
- Presos de ETA rechazan una marcha en su apoyo de los ultras de Athletic, Real, Osasuna, Alavés y Eibar ↗
El Independiente · Mikel Segovia · 11 December 2019
2019 call in which Real Sociedad Firm appears.
- Video: Real Sociedad ultras attack Roma fans' bus ↗
Football Italia · Lorenzo Bettoni · 16 March 2023
Media attribution of the 2023 attack on the Roma bus.
- Graves incidentes de ultras en el Real Sociedad-Benfica ↗
Monesport · Joan Pol Alcaraz · 9 November 2023
Attributed participation in the fight before the November 2023 match.
- Nueve hinchas de la Real Sociedad heridos, tres apuñalados, por ultras de la Lazio en Roma ↗
Naiz · 23 January 2025
Toll of the Rome attack and the name «RS Firm».
- Aficionados de la Real Sociedad son apuñalados en Italia tras ataque de ultras de la Lazio ↗
El Imparcial · Patrizio Caro · 23 January 2025
Attribution of ideology and premeditation of the attack.
- La Policia incauta armas a ultras de la Real Sociedad en la previa de la final de Copa del Rey ↗
Estoesatleti · 18 April 2026
Identification and removal in Seville, ideology and relationships attributed (Atlético-leaning outlet).
Documentary review: 18 October 2026. English edition: 21 October 2026. Editorial team: Mundo Ultras.
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