Updated from 1:40 p.m. EDT

Apple ( AAPL) shares sagged lower for the second day in a row after a sharp rally earlier in the week sparked by the fevered iPhone debut at San Francisco's MacWorld.

The stock was recently trading at $94.37 after shedding 1.5%, or $1.43.

Weighing on the stock Friday was a report that federal investigators are probing a falsified stock option grant for 7.5 million options to CEO Steve Jobs approved by Apple's board in October 2001, according to The Wall Street Journal.

The board didn't actually meet that month, the report said, and investigators want to talk to two former Apple attorneys who allegedly falsified the date of the grant.

Apple conducted its own internal investigation into its stock options practices, and it is also under scrutiny by the Securities and Exchange Commission and the U.S. attorney.

In a 10-K filed with the SEC in December, Apple said it would pay $84 million in charges related to the backdating, and the board issued a statement that it believes the stock option problems are corrected and that it has "complete confidence in Steve Jobs and the senior management team."

The misstated grant date to Jobs resulted in a charge of $20 million out of the $84 million Apple is paying related to stock options manipulations.

"It's still kind of uncertain as to whether Jobs was involved in any backdating of his own grant or the manufacture of a mythical board meeting," says Paul Hodgson, a senior research associate at The Corporate Library. "We're not any closer to knowing."

"With each piece of news the market is going to react because they seem to think that without Jobs, Apple is over," Hodgson says. Apple has "been very careful in trying to distance him from the two grants to which he's associated with, only one of which was significantly backdated."

Until the investigation is officially closed by federal authorities, the stock options probe "will remain an overhang on the stock and the No. 1 question will remain: Will Steve Jobs be forced to leave the company?" says Jonathan Hoopes, an analyst with ThinkEquity. "I still believe he's sticking around."

Hoopes does not own Apple shares and his firm does not do banking.

In October, the company admitted that some grants were incorrect. Jobs knew of favorable grants, Apple said, but he didn't benefit personally and "was unaware of the accounting implications."

"There's still some unanswered questions there, or some facts that weren't set before the shareholders, and I think they need to come completely clean with those," Hodgson says. "Honesty is always the best policy."

Also this week, Apple was slapped with a trademark infringement lawsuit from networking giant Cisco ( CSCO) for using the iPhone name without its permission.

Cisco said the two companies were in discussions over the use of the name but that Apple announced the iPhone before any agreement was made.

Cisco acquired Infogear in 2000, which registered the iPhone trademark in 1996. Cisco's Linksys division has sold iPhone products since early 2006.

Apple spokeswoman Natalie Kerris called the lawsuit "silly."

"There are already several companies using the name iPhone for voice-over-IP products," Kerris said. "If Cisco wants to challenge us on it, we're very confident we will prevail."