[6] In December 2002, Celgene acquired Anthrogenesis, a privately held New Jersey–based biotherapeutics company and cord blood banking business, which is developing technology for the recovery of stem cells from placental tissues following the completion of full-term successful pregnancies.

[12] In November 2011, Celgene relocated its United Kingdom headquarters from Windsor, Berkshire, to Stockley Park, near Heathrow airport which is also the home of GlaxoSmithKline's UK operations.

[14] Citing a market capitalization of US$67 billion, and stock appreciation of 107%, Celgene was Forbes Magazine's number 2 ranked drug company of 2013.

[19] In April 2015, Celgene announced a collaboration with AstraZeneca, worth $450 million, to study their Phase III immuno-oncology drug candidate MEDI4736.

[22] In June 2015, Celgene announced it had licensed Lyceras RORgamma agonist portfolio for up to $105 million to develop its Phase I lead compound LYC-30937 for the treatment of inflammatory bowel disease.

[28] In January 2018, Celgene announced it would acquire Impact Biomedicines for $7 billion, adding fedratinib, a kinase inhibitor with potential to treat myelofibrosis.

[40] The activist investor Starboard Value LP opposed the deal, nominating five alternative potential directors on the Bristol-Myers board.

[46] In July 1998, Celgene received approval from the FDA to market Thalomid for the acute treatment of the cutaneous manifestations of moderate to severe ENL.

[50] In May 2006, Celgene received approval for Thalomid in combination with dexamethasone for the treatment of patients with newly diagnosed multiple myeloma.

Dr. Reddy's Laboratories sought the material for bioequivalency studies required to bring its own, generic, version of thalidomide to market.

In response to the refusal, Dr. Reddy's Laboratories filed a Citizen's Petition with the FDA asking the Agency to adopt procedures that would ensure generic applicants the right to buy sufficient samples to perform bioequivalence testing of drugs that were subject to REMS distribution restrictions.

Celgene further argued that requiring innovator companies to sell their products to potential generic competitors would violate its intellectual property rights and subject it to liability risks in the event that patients were harmed in Dr. Reddy's studies.

In 2018, Celgene was at the top of a list of companies that the FDA identified as refusing to release samples to competitors to create generics.

[53] Generic manufacturer Lannett Company initiated antitrust litigation that accused Celgene of using its REMS for THALOMID (thalidomide) to violate the anti-monopolization provisions of the Sherman Act.