May 5 (Reuters) - The following are the top stories on the New York Times business pages. Reuters has not verified these stories and does not vouch for their accuracy.
* Even after a year post Tumblr's acquisition by Yahoo! Inc , the biggest issue bothering Tumblr's Chief Executive David Karp is: how to generate significant revenue growth from the blogging service. But rather than slap banner ads and risk a mutiny from users, the company is working with advertisers to encourage them to create their own Tumblr pages and come up with creative material - also known as native advertising - that fans can interact with. (r.reuters.com/teq98v)
* HBO's popular TV series Game of Thrones has generated a lot of buzz among its coveted demographic of younger, wealthier viewers. But with no televised advertisements during the show, companies are trying to reach viewers through their smartphones, tablets and laptops with social media posts. (r.reuters.com/veq98v)
* John Heilemann and Mark Halperin, political journalists known for their books on the past two presidential campaigns, will join Bloomberg in the coming days to start a new site that will focus on American politics and policy. (r.reuters.com/xeq98v)
* Created 25 years ago to provide movie listings on phone, Moviefone is set to re-launch as a free app and a website on Monday. Moviefone makes money mostly by selling advertising, which is shared by AOL Inc and Whalerock. AOL said that Moviefone has about 10 million users. (r.reuters.com/cuq98v)
* Hedge fund Greenlight Capital has requested the Securities and Exchange Commission for confidential treatment of its buying strategy on Micron Technology Inc. The firm said disclosure of its buying strategy on Micron would cause "substantial" financial harm to its investors because the hedge fund intended to keep accumulating shares for at least another week. (r.reuters.com/guq98v)
* Portugal announced its exit from a three-year bailout program that has forced deep spending cuts and set off mass protests. Prime Minister Pedro Passos Coelho said that Portugal had built up sufficient financial reserves to end the program on schedule, without requesting any additional line of credit from its European counterparts. (r.reuters.com/juq98v)
* Ukraine has been pushing hard to start reverse-flow deliveries of gas from Europe via Slovakia to Ukraine, thus blunting repeated Russian threats to turn off the gas tap. An agreement signed last week between Slovak and Ukrainian pipeline operators opened the way for modest reverse-flow deliveries of gas from Europe, where prices are much lower than those demanded by Gazprom for its direct sales to Ukraine. (r.reuters.com/kuq98v) (Compiled by Ankush Sharma in Bangalore)