Shares in Quest Diagnostics spike 20% after brief trading halt

Shares in Quest Diagnostics spiked as much as 20.5 percent Friday morning after a brief trading halt, which followed a sharp move in the shares earlier in the session.

Traders appeared to be linking the move to unconfirmed market chatter surrounding the stock. Dow Jones reported the chatter was linked to buyout talk.

Quest was not immediately available for comment.

Shares gave back most of their gains after the initial spike, and by 10:55 a.m. ET were up just under 7 percent.

This story is developing. Please check back for further updates.

for the latest on the markets.