Earlier this week S&P Dow Jones Indices, along with MSCI, announced real estate investment trusts (REITs) will be separated into their own sector under the Global Industry Classification Standard (GICS®). The current REITs contained within the S&P 500 Index are noted in the below spreadsheet.
This change will increase the number of GICS sectors to eleven from the current ten. In a post on S&P's website they note,
"Real Estate, previously part of the GICS financial sector, will be the 11th sector while the financials will now be limited to financial services such as banking, insurance or exchanges. This is the first time since GICS was launched in 1999 that a new sector is being added."