Airbnb (NASDAQ:ABNB) saw a 5.1% increase in after-hours trading on Friday, while Blackstone (NYSE:BX) experienced a 4.3% rise following the announcement that both stocks would join the prestigious S&P 500 index.

S&P Dow Jones Indices disclosed that as part of its quarterly rebalancing, Blackstone will replace Lincoln National (LNC), which will now be included in the SmallCap 600 index. Similarly, Airbnb will replace Newell Brands (NWL), which is also moving to the SmallCap 600. Lincoln National (LNC) experienced a 1.8% decline, and Newell Brands (NWL) slipped by 3%.

In addition to this, several companies have been added to the S&P MidCap 400, including Permian Resources (PR) with a 4.4% surge in after-hours trading; Gaming & Leisure Properties (GLPI) with a 1.6% increase; GoDaddy (GDDY) with a 2.6% boost; Morningstar (MORN) with a 4.4% rise; Ally Financial (ALLY) with a 2.8% jump; Vistra (VST) with a 4.2% increase; Vail Resorts (MTN) with a 2.3% surge; Sensata Technologies (ST) with a 4.6% rise; Weatherford International (WFRD) with a 4.3% increase; Fidelity National Financing (FNF) with a 3.6% boost; and RBC Bearings (RBC) with a 2.4% rise.

Conversely, the following companies will move from the MidCap 400 down to the SmallCap 600: Omnicell (OMCL), Papa John’s International (PZZA), Sensient Technologies (SXT), Cathay General Bancorp (CATY), Energizer Holdings (ENR), Xerox Holdings (XRX), Highwoods Properties (HIW), Tripadvisor (TRIP), JetBlue Airways (JBLU), and Foot Locker (FL).

Exiting the SmallCap 600 are Uniqure (QURE) with a 2.5% decrease; Universal Insurance Holdings (UVE) with a 4.7% decline; Trinseo (TSE) with a 2.5% drop; The Aaron’s Co. (AAN) with a 3.8% decrease; Netgear (NTGR) with a 2.5% decline; Coherus Biosciences (CHRS) with a 1.8% drop; 8×8 (EGHT) with a 2.9% decrease; Office Properties Income Trust (OPI) with a 1.6% increase; AngioDynamics (ANGO) with a 2.5% decline; Vanda Pharmaceuticals (VNDA) with a 2.7% decrease; Orion Office REIT (ONL) with a 2.4% drop; Enanta Pharmaceuticals (ENTA) with a 3.4% decrease; FutureFuel (FF) with a 2.4% drop; RE/MAX Holdings (RMAX) with a 4.3% decline; Zynex (ZYXI) with a 1.7% drop; Anika Therapeutics (ANIK) with a 2% decrease; and Computer Programs Systems (CPSI) with a 3.1% drop.

These changes will take effect prior to the opening of trading on Monday, September 18th.