In a letter sent Monday, Clearwire Executive Chairman John Stanton reiterated his company’s struggles and the paucity of alternatives to Sprint’s proposed $2.97 per share offer to buy up the half of Clearwire it doesn’t presently own. 

Today’s letter goes over the points outlined in a letter Clearwire sent to shareholders last week but this time, Clearwire comes armed with a new recommendation from Institutional Shareholder Services (ISS), an advisory firm that is now recommending Clearwire shareholders vote for the Sprint merger.

ISS recently displayed how much influence one of its recommendations can have. In the recently finalized T-Mobile, MetroPCS merger, ISS advised MetroPCS shareholders to reject the deal, a decision which in part lead to T-Mobile parent company Deutsche Telekom sweetening the offer.

Egan-Jones Ratings Company also threw its recommendation behind Sprint’s offer, prompting Clearwire to issue a separate statement.

“As noted previously, these recommendations affirm the conclusion of a rigorous multi-year strategic review and reinforce the board’s unanimous belief that this combination is the best strategic alternative for Clearwire’s minority stockholders, delivering certain, fair and attractive value,” Clearwire said in the statement.

Still, outspoken Clearwire shareholders like Crest Financial Limited appear ready to vote against the merger when the scheduled May 21 voting meeting comes around. Crest recently filed in Delaware to perfect its appraisal rights of its Clearwire common stock, something that cannot be done unless a shareholder votes against the merger.