(Updates with details, weightings)
NEW YORK May 14 (Reuters) - Equity index provider MSCI reclassified equities across a broad spectrum of markets on Wednesday as part of its semi-annual review, adding among others U.S. social networking company Twitter Inc to its world index.
It reclassified Qatar and United Arab Emirates to emerging market from frontier-market status as expected. Qatar will have a 0.47 percent weighting in the MSCI Emerging Market index , while UAE will have 0.58 percent.
About $8 trillion is benchmarked to MSCI indexes. The emerging markets index is up 2.9 percent so far this year, while the all world index has risen 2.1 percent.
Twitter is one of the biggest additions to the MSCI All World index, which will add 58 companies and eliminate 45 at the end of May.
MSCI added 10 Qatar companies and nine UAE companies to the all world index and to the emerging markets index.
Qatar National Bank SAQ, Industries Qatar QSC and National Bank of Abu Dhabi PJSC will be the biggest additions to the emerging market index.
The MSCI China A index will get Shanghai Raas Blood Products Co Ltd, Shanghai Waigaoqiao Free Trade Zone Development Co Ltd and Dongxu Optoelectronic Technology Co Ltd.
In all, 13 securities will be added to the MSCI China A Index, while 33 will be deleted.
Thirteen securities will be added to the MSCI Frontier Markets Index and 30 will be deleted. Two of the largest additions will be from Pakistan - Pakistan Tobacco Company Ltd and K-Electric Ltd.
All changes will be implemented as of the close on May 30. (Reporting by Caroline Valetkevitch. Editing by Andre Grenon)