Rizvi and his clients hold a 15% stake in the San Francisco-based firm.
Three top investors in Microsoft call for chairman Bill Gates to step down.
Potential NYSE listing to value the microblogging service at around $16bn.
Alibaba decided to list in the US, instead of Hong Kong, to gain corporate structure privileges
E-commerce giant could raise about $12.9bn through the IPO.
Vodafone must secure 75% of Kabel Deutschland's shares to complete €7.7bn deal.
Public outcry as UK-based phone giant avoids UK tax after one of biggest corporate deals in history
Market capitalisation increases by about $10bn in one month.
Samsung loses over $1bn in market value following US veto, as South Korea's concerns branded 'absurd' by expert.
Sony swings to profit in first quarter helped by weak yen and better sales of Xperia smartphones.
Facebook's stock price rises 7% in heavy trading on Tuesday.
BioWare Montreal development team hints at new, exciting storyline without Commander Shepard.
Stock surges by nearly 15% in early trade on Friday.
Mexican telecoms giant America Movil moves in on UK's music recognition industry.
Sales rise 15.6% during the first-half.
Mass Effect 4 to feature core system of Dragon Age 3: Inquisition.
Barclays, Citigroup, CLSA, Goldman Sachs and Morgan Stanley welcome Infosys' co-founder's return.
Murthy takes his son, Rohan Murthy, as executive assistant for five-year period.
Apple raises prices of iPads and iPods in Japan following yen fall.
The Bangalore-based firm is already contesting previous tax demands for financial years 2005 to 2008.
The EU is planning to launch a formal investigation against Huawei and ZTE.
Tumblr feels the offer as "too low" and views it as "only a first offer".
Net profit declines 79% to $130m amid investors' battle to takeover the company.
BioWare executive producer and lead developers examine potential characters to star in upcoming Mass Effect spin-offs.
Icahn and Southeastern, who were opposing the $24.4bn deal for Dell, come up alternative offer.
Strong demand for chips from manufacturers of smartphones and tablets help the company's results.
Samsung has come under fire for posting fake negative reviews of rival HTC smartphones on Taiwanese websites.
The tech majors report higher quarterly profits, despite problems related to the fast changes in the sector.
Sony looks to recover from four straight yearly losses with the sale of its New York City headquarters.
HP accuses Autonomy of serious accounting improprieties and disclosure failures.