Proxy advisory firms yesterday issued conflicting opinions on Sprint Nextel’s proposed takeover of Clearwire, with ISS advising Clearwire shareholders to vote in favor of the deal and Glass Lewis urging them to vote against it.

Clearwire shares were down 2 cents, to $3.25, at close yesterday. Sprint shares were up a penny, at $7.36.

Sprint already owns just over 50 percent of Clearwire’s shares and has agreed to pay $2.97 per share for the rest.

Clearwire stockholders will vote on May 21.