Inclusion Criteria:

• Participants who are scheduled to be treated with epcoritamab for Treatment after two or more prior lines of therapy 3L+ diffuse large B-cell lymphoma ((D)LBCL) or 3L+ Follicular lymphoma (FL).
• Treatment with epcoritamab should be administered in accordance with the approved local label in the participating country.
• The decision to treat the participant should have been made by the clinician prior to, and independently of any decision to approach the participant to participate in this study.

Exclusion Criteria:

• Any condition included in the contraindications section of the approved local epcoritamab label in the participating country.
• Participation in a concurrent interventional clinical trial (not including non-interventional/ observational study, PMOS, or registry participation) from enrollment and throughout the study.