UPDATED: With vote approaching, Perrigo chief slams Mylan's 'troubling' values

There are just three days left until Mylan's ($MYL) shareholders decide whether the company should push forward with its hostile pursuit of Perrigo. And just in case they do, Perrigo is making sure its own shareholders are ready to shoot it down.

Perrigo CEO Joseph Papa

As CEO Joseph Papa wrote in a letter to investors Tuesday, Perrigo's execs "believe deeply in our responsibility to shareholders, who are Perrigo's true owners, and in our obligation to build sustainable, long-term value, which informs everything we do."

Mylan's execs, though? That's a different story, he wrote. "Mylan's pursuit of Perrigo at all costs has … highlighted some very troubling corporate governance values," he said--citing the company's move to lower the deal acceptance condition from 80% to 50%, and threats to delist Perrigo shares even if 49% of its investors don't like Mylan's offer.

To Papa and Perrigo, that's an "unacceptable" way to treat shareholders and run a company, he said.

He's not the only one who feels that way. Earlier this month, proxy adviser ISS issued a report to clients recommending they vote against the tie-up. The way ISS sees it, lowering the threshold to 50% increased the risk that Mylan gets stuck as a large shareholder in a public company without a clear path to obtaining the rest.

"The transaction Mylan envisions may indeed be a solid business strategy. What it has asked shareholders to approve at this meeting, however, is not a compelling acquisition strategy," ISS wrote.

Mylan, of course, has stood by its offer, touting "sound strategic and financial rationale." And "at Mylan, we believe the greatest evidence of commitment to shareholders is creating significant and sustainable value for the company," Chairman Robert Coury said in a Thursday statement.

However Perrigo feels about Mylan's proposal, though, it better watch its words. Three of the company's statements from earlier this month ran afoul of the Irish Takeover Panel's rules, the body announced Thursday.

- read Papa's letter (PDF)
- read Mylan's release
- see the Irish Takeover Panel's statement

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