The primary objective of the study is to estimate the incidence rate of serious adverse events (SAEs), including but not limited to malignancies and serious and opportunistic infections, among participants with MS treated with Vumerity, Tecfidera, other selected disease modifying therapies (DMTs \[teriflunomide, beta interferons, or glatiramer acetate\]), or Vumerity after switching from Tecfidera. The secondary objective of the study is to compare the incidence rate of SAEs, including but not limited to malignancies and serious and opportunistic infections, among MS participants treated with Vumerity, Tecfidera, and Vumerity after switching from Tecfidera with the incidence rate of MS participants treated with other selected DMTs (teriflunomide, beta-interferons, or glatiramer acetate), if the sample size allows.