UPDATE 1-Williams to buy rest of Williams Partners in $10.5 bln deal

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May 17 (Reuters) - Pipeline operator Williams Cos said on Thursday it would buy the remaining 26 percent stake that it does not already own in its master limited partnership, William Partners LP, for $10.5 billion. Williams would give 1.494 of its shares for each share of Williams Partners, with the offer representing a premium of 6.4 percent based on Wednesday’s closing price.

The company said the deal will immediately add to cash available to dividends extending the period for which the company is not expected to be cash taxpayer through 2024.

The deal simplifies Williams’ corporate structure, streamlines governance and maintains investment-grade credit ratings, the company said.

Shares of Williams Companies were up 2.3 percent to $28 in premarket trading. (Reporting by Akshara P in Bengaluru; Editing by Gopakumar Warrier and Shailesh Kuber)