LEADING THE DAY: The House Judiciary Committee will meet Thursday to markup the controversial Stop Online Piracy Act (SOPA) and vote on the manager’s amendment from Rep. Lamar Smith (R-Texas), which seeks to address some of the criticism about the bill.

On Wednesday, founders of several high-profile tech companies including Google, Twitter and Wikipedia wrote an open letter to Washington lawmakers asking that SOPA and its Senate companion, PIPA, be changed before they are passed. A draft of an alternative bill, the OPEN Act, has been circulating online and it’s expected that Rep. Darrell Issa (R-Calif.) will introduce the bill sometime this week.

Carrier IQ: The Federal Trade Commission is looking into allegations that Carrier IQ software has tracked user activity and sent the data to cellphone companies without informing officials, The Washington Post reported Wednesday.

This week, Carrier IQ said it sought meetings with the FTC and FCC to answer questions about its software, but was not aware of any formal investigation. The company has said that its software is not designed to capture keystrokes or the content of messages but that in some cases that might have happened by accident. The software is designed to report network diagnostic information to carriers.

LightSquared: Federal officials said Wednesday that LightSquared’s proposed mobile satellite network would interfere with “the majority” of global positioning system receivers and pose dangerous disruption to airline safety systems, The Washington Post reported.

The findings resulted from testing by aviation and defense agencies and other federal officials. LightSquared CEO Sanjiv Ahuja said the company disagrees with some of the findings, but it will work with the Federal Aviation Administration to resolve the issues.

ICANN hearing: House lawmakers told the Internet Corporation for Assigned Names and Numbers (ICANN) that it should slow down on its proposal to expand Web suffixes.

ICANN, which has said that the expansion will lead to online innovation, has been working on its proposal for six years, but has faced criticism from advertisers and businesses who worry about the potential costs of defensive domain names. In his testimony at a Thursday hearing, ICANN senior vice president Kurt Pritz said that any applications for a new top-level domain would go through strict screening. He did not directly respond to a question from Rep. Anna Eshoo (D-Calif.) asking what ICANN would do if formally asked to delay its plan.

Bill Gates said he won’t return to Microsoft: Bill Gates said that he will not return to Microsoft, effectively quashing rumors that the company co-founder would take back the helm from current chief executive Steve Ballmer.

Fortune reported Monday that Gates was said to be mulling a return to Microsoft after some investors raised doubts about Ballmer’s ability to lead.

In an interview published in the Sydney Morning Herald, Gates said, “I'm part-time involved with Microsoft, including even being in touch this week to give some of my advice, but that's not going to change – the foundation requires all of my energy and we feel we're having a great impact.”

Spectrum bill: Federal Communications Chairman Julius Genachowski criticized a proposal for spectrum reform included in the House payroll tax holiday package, saying that some measures would “tie the agency’s hands.” The proposal, introduced by Rep. Greg Walden (R-Ore.), allocates the D-Block of spectrum for a public-safety network but does not allow the FCC to set aside spectrum for unlicensed use.

“I encourage Congress to leave no doubt that the FCC can continue its policies to promote unlicensed spectrum use alongside licensed uses,” Genachowski said.

On Wednesday, Reps. Eddie Bernice Johnson (D-Texas) and Donna Edwards (D-Md.) introduced a bill that would allocate $300 million to research the creation of a public-safety network.