(Reuters) – The S&P Dow Jones Indices said on Friday server maker Dell Technologies, data analytics firm Palantir Technologies and property and casualty insurer Erie Indemnity will join the benchmark S&P 500 before the market opens on Sept. 23.

Shares of Palantir rose nearly 8% in extended trading, while those of Dell and Erie rose 6% and 3%, respectively.

The three companies will replace American Airlines Group, online marketplace Etsy and diagnostics company Bio-Rad Laboratories in the index.

Shares of American Airlines were down 0.7%, while those of Bio-Rad Laboratories and Etsy fell about 1%.

(Reporting by Zaheer Kachwala in Bengaluru; Editing by Shinjini Ganguli)