S&P 500 Index
The S&P 500 Index, considered to be the world's leading benchmark for institutional investors, is an index owned and maintained by Standard & Poor's Corp. It is composed of 500 publicly held, predominantly U.S. corporations, all of which are considered "large caps." All stocks in the S&P 500 index are traded on the New York Stock Exchange and NASDAQ. More than $1.3tn of assets directly track or are benchmarked against the index.
Entry into the S&P 500 can be market moving for a stock.
The Standard & Poor's 500 Index is capitalization weighted, e.g., component companies weighted according to the total market value of their outstanding shares. The impact of a component's price change is proportional to the issue's total market value, which is the share price times the number of shares outstanding. These are summed for all 500 stocks and divided by a predetermined base value. The base value for the S&P 500 Index is adjusted to reflect changes in capitalization resulting from mergers, acquisitions, stock rights, substitutions, etc.
In short, S&P 500 Index components exhibit the following characteristics:
- Market Coverage – Approximately 75 percent of the U.S. equities market
- Weighting – Market capitalization
- Market Capitalization – Minimum of US$ 5 billion
- Public Float – At least 50%
- Reconstitution – On an as-needed basis
In May of 2010, the Chicago Board Options Exchange (CBOE) and its longtime rival, the International Securities Exchange (ISE), traded charges in a long-running dispute over who had the right to trade options contracts tied to major stock indexes. The CBOE and stock-index developers sought to defend in a Chicago court against arguments that the ISE ought to be able to list options on stock market benchmarks like the S&P 500, despite the CBOE's long-held licenses on the indexes. CBOE began trading stock index options in 1983, but in November 2006 the ISE sought a judgment in New York that would let it offer its own contracts on the S&P 500 and Dow Jones Industrial Average without obtaining licenses from the index developers.
On May 13, 2013, the U.S. Supreme Court turned down an appeal by Deutsche Boerse (owner of the ISE) to overturn lower court rulings restraining the ISE from trading the S&P 500 Index.  Since there is no appeal beyond the U.S. Supreme Court (in the United States), that was the end for this particular piece of litigation.
On May 3, 2013, the S&P 500 went beyond 1,600 points for the first time closing at 1,614.42.
CBOE Options on S&P 500 Index (SPX) Overview
On March 9, 2015, the CBOE expanded trading hours for the SPX options, adding more than six hours of additional trading five days a week. The extended hours for SPX options run Monday through Friday, beginning each day at 2:00 a.m. CT and ending at 8:15 a.m. CT. The 2:00 a.m. CT start in Chicago syncs with the 8:00 a.m. open of trading in London.
In April 2021 the Cboe said it would again expanded global trading hours for S&P 500 index options as well as Cboe volatility index (VIX) options in the fourth quarter of 2021, subject to a regulatory review.
CME Group S&P 500 Contract Overview
In futures, CME introduced trading in S&P 500 futures in 1982, a few years later adding options on the index. In 1997, CME launched trading in the E-mini S&P 500 futures contract which, due to its broad appeal and electronic focus, now trades more than the larger sized S&P 500 futures contract.
|Trade Unit||$250 times the Standard & Poor's 500 Stock Price Index|
|Point Descriptions||1 point = .01 index points = $2.50|
|Contract Listing||8 months in the March quarterly cycle. Mar, Jun, Sep, Dec.|
|Floor Trading Hours||8:30 a.m.-3:15 p.m. Month end(3:15 p.m.) LTD(3:15 p.m.)|
|Minimum Fluctuation, Floor Trading||0.10=$25.00|
|Globex Hours||Mon/Thurs 5:00 p.m.-8:15 a.m. & 3:30 p.m.-4:30 p.m.; Shutdown period from 4:30 p.m. to 5:00 p.m. nightly; Sun & Hol 5:00 p.m.-8:15 a.m.|
|Minimum Fluctuation, Globex||0.10=$25.00|
- Standard & Poor's Corp. for other indices.
- Entry into S&P 500 could be influenced by ratings sales, research suggests. The Financial Times.
- S&P 500: pay to play?. The Financial Times.
- "S&P 500”. Standard & Poor's.
- "S&P 500 Factsheet”. Standard & Poor's.
- Options Exchanges Spar Over Stock Indexes In Illinois Court. Nasdaq.
- Deutsche Boerse Unit Spurned by Court on Index Options. Bloomberg.
- What's Beyond the S&P 500's Relentless Rally. CNBC.
- "CBOE contract specs". Chicago Board Options Exchange.
- CBOE Set to Expand VIX and SPX Options Trading Hours in Early March. CBOE.
- Cboe extends options trading to almost 24 hours-a-day. The Trade.
- "CME contract specs". CME Group.