June 10 (Reuters) - Bitcoin miner Bitfarms ( BITF )

said on Monday it had approved the adoption of a "poison pill"

to fend off a potential hostile takeover attempt by rival Riot

Platforms ( RIOT ).

The move comes days after Riot Platforms ( RIOT ) disclosed it had

built a 12% stake in Bitfarms ( BITF ) as it pursues a takeover attempt.

Riot had offered to buy Bitfarms ( BITF ) for about $950 million last

month.

Bitfarms ( BITF ) said the shareholder rights plan aimed to

preserve the integrity of its previously announced strategic

alternatives review process.

Poison pill plans, including shareholder rights plans,

are used by corporate boards to thwart hostile takeover bids.

Under Bitfarm's plan, if an entity accumulates more than

15% of Bitfarms' ( BITF ) stake after June 20 and up to Sept. 10, the

company would issue fresh shares, diluting the entity's stake.

After Sept. 10, the threshold would be relaxed to 20% as

long as any takeover attempt meets certain conditions.