See which companies are making the headlines even before the bell rings.

Biogen (BIIB) – Biogen slid 6.5% in the premarket after SamsungKorea Economic Daily reported that Biogen denied being in discussions to acquire Biogen and combine the biotech business with it. Biogen shares rose 9.5% on Wednesday following the report.

JetBlue (JBLU) – The airline cut nearly 1,300 flights from its schedule through January 13, as it deals with a surge in Covid-19 infections among its flight staff. JetBlue’s premarket actions were down by 1%.

Didi Global (DIDI) – The China-based ride-hailing company’s shares slid 3.2% in premarket trading after it reported a 1.7% decline in third-quarter revenue and a loss of $4.7 billion, stemming from a regulatory crackdown. Didi’s shares fell 8.2% on Wednesday, and have fallen 12 times in the last 15 trading days.

R.R. Donnelley (RRD) – The business communications and marketing services company received an unsolicited, non-binding acquisition proposal at $11 per share in cash. R.R. R.R. Premarket trading saw Donnelley shares rise 3.1%

Virgin Orbit (VORB) – The satellite-launching spin-off of space travel company Virgin GalacticVirgin Orbit ticker and name will be traded on Nasdaq immediately after shareholders of blank check company. NextGen Acquisition Corp. IIThe merger was approved earlier in the week.

Micron Technology (MU) – The memory chip maker’s stock lost 1.5% in the premarket after it warned that Covid-19 curbs in China’s Xian tech hub would impact production. Samsung Electronics – which is also one of the world’s biggest memory chip makers, issued a similar warning.

Johnson & Johnson (JNJ) – A booster dose of the J&J Covid-19 vaccine was found to be 85% effective in preventing hospitalizations in a South African study, which has yet to be peer-reviewed.

Microstrategy (MSTR) – The business analytics company’s stock rose 1.1% in the premarket, tracking a rise in bitcoin prices. Microstrategy’s balance sheet includes bitcoin holdings in excess of several billion dollars.