Today: Carl Icahn pushes Apple (AAPL) CEO Tim Cook to increase stock buyback program while his Netflix (NFLX) investment continues to pay off. Also: Wall Street gains despite government shutdown, with tech stocks leading the way.

The Lead: Apple and Netflix investments help Icahn, but he wants more

Activist investor Carl Icahn is making plenty of money from his big Silicon Valley investment of 2012, Netflix, but he is pushing for payback on his big 2013 bet of $2 billion on Apple, calling a larger share-buyback plan a "no-brainer."

Icahn tweeted Tuesday that he asked Apple CEO Tim Cook to increase the Cupertino tech giant's stock-repurchase program to $150 billion during a dinner the two shared Monday evening. Cook announced in April a plan to return $100 billion to the company's shareholders, who have withstood a drop in Apple's share prices from highs of more than $700 hit in Sept. 2012 to lows of less than $400 in 2013; $60 billion of that plan involves Apple repurchasing shares from investors like Icahn.

"I feel very strongly about this," Icahn told CNBC in a Tuesday interview. "I can't promise you the stock will go up and I can't promise you they will do the buyback. But I can promise you that I'm not going away until they hear a lot more from me concerning this."

Icahn also said in the CNBC interview that his fund has built up a $2 billion investment in Apple, after originally announcing a purchase of about $1 billion of shares in August. While that represents about a half a percent of Apple's market cap, it was apparently enough to get Apple's top executives to visit his New York home for a dinner.

As is typical when Icahn tweets about a company, shares zoomed higher. Apple stock gained 2.4 percent to $487.96 Tuesday, with a noticeable spike occurring midway through the morning session, when Icahn's tweet arrived. That is less of a bump than the day Icahn announced his original investment in Apple, but the endpoint is similar: Apple shares gained 4.8 percent that day to $489.57.

Repurchasing more shares would decrease the amount of available Apple stock on the public markets, likely boosting Apple's share price in the short term, though the actual effect of increasing the buyback from $60 billion to $150 billion is not a given. Icahn termed it a "no-brainer" because of the company's strong underlying metrics and low interest rates available for Apple's to borrow money.

"They have a golden opportunity to go borrow money," Icahn told CNBC.

Analysts aren't so sure that increasing the buyback would be good for Apple's businesses: JMP Securities analyst Alex Gauna told Bloomberg News that Apple needs to focus more on revenues.

"To justify the valuation on the stock, it's got to get back to earnings growth. They have to be always innovating and putting in place the mechanisms for growth, or it doesn't matter how much cash they return to shareholders," he said.

While Apple's share price is still relatively near the same price as when Icahn, a prominent voice in the investment community since a hostile takeover of TWA in 1985, began scooping up stock, the same can't be said for the investor's other Silicon Valley gambit, Netflix. On the day that he filed notice of ownership of 5.4 million shares in Netflix, the Los Gatos video-on-demand service's stock jumped 13.9 percent to $79.24; Tuesday, Netflix shares again hit record intraday and closing prices, moving as high as $324.70 before closing with a 5 percent gain at $324.62.

Netflix shares may have received a boost from a pair of positive reports. Janney Capital wrote Monday night that Web usage shows Netflix is growing internationally and is receiving "a very high level of interest in its originals that is on par with major hit pay TV shows," with "originals" referring to the company's self-produced shows such as "House of Cards" and "Orange is the New Black." MKM Partners analyst Rob Sanderson followed that report Tuesday morning by writing that Netflix international subscription growth could eclipse the company's forecasts and propel Netflix in the future.

"We continue to think international subs will surprise and eventually be as large (or larger) than domestic," Sanderson wrote.

Despite massive gains, Icahn said Tuesday he has not sold any Netflix stock. He is growing more pessimistic, however, using the same language as he did for Apple with a different meaning.

"(Netflix is) not the no-brainer that it was when we first bought it," he said.

SV150 market report: Wall Street shrugs off shutdown, tech stocks lead the way

A day after declines blamed on an impending shutdown of the federal government, stocks zoomed higher on the first day of select closures due to the partisan wrangling in Washington. Technology stocks were some of main beneficiaries of Tuesday's investor largesse, with the tech-heavy Nasdaq leading Wall Street's main indexes with a 1.2 percent gain and the SV150 coming in right behind with a 1.1 percent increase.

Yelp, which gained more than 90 percent in the third quarter, started the fourth quarter off with a bang, increasing 7.5 percent to a record closing price of $71.12 after Cowen and Co. analysts bumped up their price target on the stock from $60 to $80 and Needham analysts reiterated their price target of $78 in Tuesday notes to clients. Yahoo (YHOO) hit its highest intraday and closing prices in more than five years, surpassing the $34 mark and closing with a 3.4 percent increase to $34.31. The Sunnyvale Internet company, which is waiting for Asian investment Alibaba to file for a U.S. initial public offering, received a price target boost to $39 from Citi analyst Mark May, who noted the coming Alibaba payoff as well as "encouraging signs that the new management team's efforts are resulting in improved user trends and mobile traction."

Google (GOOG) gained 1.3 percent to $887 after a European regulator detailed the concessions the Mountain View company has offered to make in order to avoid antitrust charges overseas. Facebook, one of only two SV150 companies to experience greater growth in the third quarter than Yelp, gained 0.4 percent to $50.42 while announcing a new ad system that will allow app makers to remind users of apps they have downloaded but are not using.

On the negative side, Intel (INTC) dropped 0.4 percent to $22.83 as reports claimed the Santa Clara chipmaker could lose the executive in charge of its television ambitions to the Hulu CEO post and that Intel had agreed to acquire a Palo Alto startup for $20 million. Cisco (CSCO) dropped 0.1 percent to $23.24 after reporting Monday afternoon that CEO John Chambers' salary had nearly doubled.

Up: Yelp, Netflix, Zynga, SunPower (SPWRA), Yahoo, SolarCity, Electronic Arts (ERTS), Apple, Workday, LinkedIn, Pandora, Hewlett-Packard (HPQ), Juniper, VMware, Salesforce, AMD, Google

Down: Palo Alto Networks, Symantec, Intel, Applied Materials, Tesla, Gilead

The SV150 index of Silicon Valley's largest tech companies: Up 14.91, or 1.12 percent, to 1,349.61

The tech-heavy Nasdaq composite index: Up 13.45, or 0.8 percent, to 1,695

The blue chip Dow Jones industrial average: Up 62.03, or 0.41 percent, to 15,191.7

And the widely watched Standard & Poor's 500 index: Up 46.5, or 1.23 percent, to 3,817.98

Check in weekday afternoons for the 60-Second Business Break, a summary of news from Mercury News staff writers, The Associated Press, Bloomberg News and other wire services. Contact Jeremy C. Owens at 408-920-5876; follow him at Twitter.com/jowens510.