MADRID, June 26 (Reuters) - Investment funds Antin

, Cinven, CVC, KKR and Permira have

filed offers to buy Spanish pharmaceutical company Rovi's

third-party manufacturing business, newspaper

Expansion reported on Wednesday citing unidentified market

sources.

The five firms filed non-binding bids on June 13 and are now

in the middle of a due diligence process for binding offers, the

newspaper reported.

Rovi said in March it had hired Lazard as an adviser for a

potential sale of the unit which has produced COVID vaccines on

behalf of Moderna, among other drugs.

The unit is estimated to be worth about 3.5 billion euros

($3.75 billion), Expansion said.

Spokespeople for Rovi, Cinven and KKR declined to comment,

while Antin, CVC and Permira did not immediately respond to

requests for comment.

($1 = 0.9344 euros)