UPDATE 2-Vivendi may sell additional 10% of shares in Universal Music

* Considers sale of a 10% block to an ‘American investor’

* Could instead list 5-10% of Universal

* Universal to be free of any ‘poison pill’ (Adds details, background)

PARIS, May 18 (Reuters) - Vivendi could sell an additional 10% of its Universal Music Group business, the label behind artists such as Lady Gaga and Taylor Swift, which the French media conglomerate is planning to list in Amsterdam.

Vivendi is seeking to cash in on its crown jewel asset, the world’s biggest music label, as the music industry benefits from growth in streaming revenues.

“The group is analysing the opportunity of selling 10% of UMG shares to an American investor or initiating a public offering (IPO) of at least 5% and up to 10% of UMG shares,” Vivendi said in a statement on Tuesday.

Universal is currently 20% owned by a consortium led by Chinese giant Tencent, following the sale of two 10% stakes. The remaining 80% is owned by Vivendi.

The group, controlled by billionaire Vincent Bollore, last week set out its plan to list Universal by Sept. 27, in a transaction that will see it distribute 60% of Universal’s capital to its current shareholders.

Vivendi values the whole of Universal at 33 billion euros ($40 billion) in its documents.

Excluding the potential sale of an additional 10% stake in Universal, Universal’s three biggest shareholders would be Vivendi (20%), the Tencent-led consortium (20%) and Bollore (16%) at the end of the IPO process.

In the event of such a sale, Vivendi would retain the remaining 10% stake for at least two years, it said in its statement.

The group also said there would be no “poison pill”, or mechanism to prevent future potential hostile takeover attempts on Universal.

The Paris-based company will also propose that Universal’s board be composed by a majority of independent directors and that shareholders be free to designate directors in accordance with majority conditions under Dutch law.

Neither Vivendi nor the family-run Group Bollore conglomerate that controls it, intend to be represented on Universal’s board, it said.

Vivendi’s statement also said Universal’s first-quarter “earnings attributable to shareowners” jumped by 62% from a year earlier to 135 million euros. ($1 = 0.8220 euros) (Reporting by Sudip Kar-Gupta and Mathieu Rosemain. Editing by Christopher Cushing, Jason Neely and Jane Merriman)