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Amid a disastrous week in the markets, a few notable companies got some publicity on Friday—and a stock pop—during a press conference with President Donald Trump.

The president ushered a lineup of “the biggest business people, the greatest retailers anywhere in the world,” Trump said on Friday, to address the spread of coronavirus—which has now become an official national emergency.

Walgreens, Walmart, Target, Becton Dickinson, Roche Diagnostics, Quest Diagnostics, CVS, LHC Group, and LabCorp all saw their stocks shoot up shortly before market close after their respective executives spoke alongside Trump during a White House press conference on Friday, addressing new measures to stem the spread of coronavirus in the U.S.

Walmart’s stock popped nearly 5% before market close, as CEO Doug McMillon addressed plans to keep parts of Walmart parking lots open per a request from the White House—giving Americans better access to its drive-through testing experience. Walgreens’ president Richard Ashworth also announced the company would continue to partner with the administration and the CDC—its stock popped 5%.

Other CEOs like Target’s Brian Cornell assured Americans the retailer would continue keeping stores open amid consumer efforts to stock up on household goods, and Becton Dickinson’s Tom Polen announced the medical device maker was “ramping up [its] manufacturing capacity” to ensure ample testing equipment was available. Quest Diagnostic’s Steve Rusckowski said the company has been working with the FDA and CDC and is “up and running” with tests in its facilities, while Roche’s Matt Sause said the company has partnered with laboratories to get a new coronavirus test approved and soon distributed. (LHC Group’s Bruce Greenstein appeared to show Trump how to bump elbows to avoid a handshake).

The group notably saw their stocks skyrocket at least 4% to 5% (and even as much as 9% for LabCorp) during the conference.

But upon watching the lineup of the big CEOs addressing the nation one after the other, some took to Twitter to suggest the president was highlighting companies to boost their stock.

He's trying to pump their stocks!
— Will Wilkinson (@willwilkinson) March 13, 2020

Despite a volatile week in the markets, major indexes like the S&P 500 and Dow rose 9% to close on Friday, with the stocks posting their biggest rally since 2008.

Stocks were pushed to session highs following an announcement from President Trump that 50,000 new coronavirus tests will be available next week.