Stocks making the biggest moves before the bell: AT&T, IBM, Crocs, Blackstone & more
Check out the companies making headlines before the bell:

AT&T (T) – AT&T rose 1.5% in premarket trading, after the company beat estimates by 9 cents with an adjusted quarterly profit of 87 cents per share. Revenue also came in above analyst forecasts, with AT&T seeing growth in demand for its phone and internet services as well as HBO and HBO Max.

Danaher (DHR) – The maker of medical and diagnostic equipment earned an adjusted $2.39 per share for the third quarter, 24 cents above estimates, with revenue also topping predictions. Danaher saw a significant contribution to results from Covid-19 testing and treatment. Shares were flat in the premarket.

Blackstone (BX) – The private equity firm stock gained 2.8% in premarket action, after earnings per share came in at $1.28, topping a consensus estimate of 91 cents. Blackstone benefited from strong investment performance, among other factors.

Dow Inc. (DOW) – The chemical maker came in 19 cents above estimates with an adjusted third-quarter profit of $2.75 per share, with revenue also above estimates. Dow saw improved performance in packaging and specialty plastics as well as coatings, and the stock rose 1.2% in premarket trading.

Quest Diagnostics (DGX) – The medical lab operator saw its shares jump 3.4% in the premarket following better-than-expected quarterly results. Quest earned an adjusted $3.96 per share, compared to a consensus estimate of $2.88 per share. The company's results got a boost from increased Covid testing, and it raised its full year outlook.

Crocs (CROX) – Crocs surged 11.1% in the premarket, following adjusted quarterly earnings of $2.47 per share compared to a $1.88 consensus estimate. The shoe maker's revenue also beat forecasts, with digital sales up 69%.

IBM (IBM) – IBM beat estimates by 2 cents with adjusted quarterly earnings of $2.52 per share, but revenue fell below analyst forecasts amid some weakness in the company's cloud business and a pullback in client spending. IBM slid 5% in premarket trading.

CSX (CSX) – CSX reported quarterly earnings of 43 cents per share, 5 cents above estimates, with the railroad operator's revenue exceeding estimates as well. The beat was driven by an increase in shipping volumes that was 3% above the strong year-ago level. CSX shares rallied 3.9% in premarket trading.

Tenet Healthcare (THC) – Tenet earned an adjusted $1.99 per share for its latest quarter, well above the $1.02 consensus estimate, and the hospital operator also reported better than expected revenue as well as raising its full-year earnings forecast. Tenet's results got a boost from increased admissions as well as a jump in revenue per admission. The stock jumped 4% in premarket action.

Unilever (UL) – Unilever gained 1.3% in premarket trading after the consumer products giant reported better than expected quarterly results. The maker of Dove soap and Hellman's mayonnaise was able to raise prices to offset higher input costs, but warned that it expects inflation was likely to accelerate in 2022.

Canadian National Railway (CNI) – The Wall Street Journal reported that activist investor Elliott Management has taken a "substantial" stake in the rail operator. Another activist investor, TCI Fund Management, already has a more than 5% stake in Canadian National. Shares were flat in the premarket.