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Pfizer discussing Allergan offer at $370-$380 per share: source

The Pfizer logo is pictured at their building in the Manhattan borough of New York October 29, 2015. REUTERS/Carlo Allegri

(Reuters) - Pfizer Inc (PFE.N) is in talks to acquire Allergan Plc (AGN.N) for $370-$380 per share, according to a person familiar with the matter, valuing the potential deal at around $150 billion, the healthcare sector's biggest.

Talks between the sides have accelerated, though the U.S. Treasury's announcement on the tightening of the rules for tax inversions has made timing more uncertain and a deal is not imminent, the source said, asking not to be identified because the matter is confidential.

Pfizer declined to comment, while Allergan did not respond to a request for comment.

(Reporting by Greg Roumeliotis in New York; Editing by Sandra Maler)