Pet supply retailer PetSmart Inc (PETM.O) disclosed on Tuesday it was in talks to acquire or merge with a privately held rival, but ended talks over competition and antitrust concerns.

PetSmart succumbed to calls from Jana Partners LLC and other large shareholders for a sale last month by agreeing to be bought by a private equity consortium led by BC Partners Ltd for $8.7 billion.

In a regulatory filing, PetSmart said Chief Executive David Lenhardt held multiple talks with the unidentified private company, but decided to exclude it as a bidder.

The company said it received interest from 27 potential buyers from mid-August to the end of October when it formally launched a search for a potential buyer after talks with the private company did not materialize.

PetSmart will hold a special meeting for shareholders to vote on the transaction, it said in the filing.

Phoenix-based PetSmart, which has about 54,000 employees and operates 1,387 pet stores, said in August it would explore a potential sale of the company.

The company's shares closed at $81.21 on Nasdaq on Tuesday.