Relations had already soured with the rival bidder, identified previously by sources familiar with the situation as French drugmaker Sanofi (SNYNF), after it went back on an initially higher bid, according to the J&J (JNJ) filing formally setting out details of the offer.

J&J’s agreement on Jan. 26 to buy Actelion (ALIOF) in an all-cash deal marked the biggest European drugs takeover in 13 years.

Although people close to the talks had told Reuters that Sanofi had gained a seat at the negotiating table, the French group has consistently declined to comment. Some investors have expressed frustration at Sanofi’s failure to land a big deal.

J&J’s prospectus for its tender offer revealed the rival bidder, identified only as “Company A”, had made a written proposal on Dec. 12 for a takeover price in cash that outbid J&J’s and which resulted in the U.S. healthcare group quitting talks.

But just a week later, the rival bidder became unwilling to proceed with talks unless Actelion considered a lower price.

“Company A indicated that it would only be willing to proceed with a transaction on the basis of a price lower than its previously communicated offer price and on different terms,” the prospectus said.

On Jan. 23, Actelion’s board discussed the merits of the competing offers and decided the financial terms of the two proposals would deliver approximately equivalent value to shareholders.

Greater Certainty

However, the filing said the board concluded: “J&J’s proposal offered significantly greater transaction certainty because the transaction documentation was nearly final and because J&J had already completed the required due diligence.”

The filing said the tender offer for the Swiss biotech company’s shares would run from March 3 to March 30.

Shares of the new research and development company being spun out of Actelion for a Swiss listing will be distributed to Actelion shareholders as a stock dividend prior to settlement of the tender offer, it said.

The prospectus also set out these details on the deal:

• Actelion will pay the bidder a $500 million break fee if the offer is not successful or does not become unconditional in certain circumstances
• The minimum acceptance rate is 67%
• J&J has agreed to make a 10-year convertible loan worth 580 million Swiss francs to the R&D pipeline company being spun off; the loan will be convertible, in two tranches, into up to 32 percent of the shares of R&D NewCo.
• R&D NewCo will be financed by the convertible loan, cash on hand of 420 million Swiss francs provided by Actelion, and a credit facility of the franc equivalent of $250 million to be provided by the bidder
• Shares of R&D NewCo are expected to be admitted to listing on the SIX Swiss Exchange on the same day as the Actelion deal settlement
• J&J intends to delist Actelion and plans a squeeze-out if needed.