Celebrated tech entrepreneurs like Jobs, PayPal's Elon Musk and Twitter's Jack Dorsey have all experienced being pushed out of their own company.
But investors don't seem to believe that CEO Jack Dorsey, who also runs mobile payments firm Square (SQ), can turn Twitter around.
Like Alibaba, it is controlled by Jack Ma, one of China's richest men.
Mr Ma has a net worth of about $20bn, according to Forbes but his success has often been overshadowed by Jack Ma of Alibaba, the e-commerce company.
On Friday morning local time Ms Chen published her very first tweet, thanking chief executive Jack Dorsey for the opportunity to be at Twitter.
Jack up the sticker price too much and the car's "affordable" tag (and sales) will be lost.
Alibaba chairman Jack Ma, a relatively recent investor in China's surging football industry, is now hoping to promote another English import after signing a development and sponsorship deal with World Rugby.
Every Jack has his Jill.
While Alibaba's Jack Ma is one of the most admired entrepreneurs in China and numbers among the richest men in the world, not many think of him when it comes to art.
When Jack bowed to someone, he always did it at lightening speed.
Preliminary results from voting in a referendum to decide if the flag would be changed were in favour of keeping the old design, which is similar to the Australian flag and incorporates the Union Jack.
I'm a police officer When my husband, Jack, was a police officer, he once approached a home guarded by two ferocious dogs.
In a legal document, FIFA admitted for the first time that South Africa's $10m payment to Jack Warner and Chuck Blazer was a bribe for World Cup votes in 2010.
Many of the officials indicted were powerful members of Fifa's executive committee, including Trinidadian strongman Jack Warner and former Brazilian football chief Ricardo Teixeira.
Jack Ma, the billionaire founder of Chinese ecommerce group Alibaba, is poised to expand his media holdings as his online finance company eyes a stake in Caixin, the business magazine.
Other Chinese billionaires in the global top 100 included Alibaba founder Jack Ma, beverage magnate Zong Qinghou, and the tech bosses at phone maker Xiaomi, social media firm Tencent and Baidu, the search engine.
Silicon Valley executives including Mark Zuckerberg, Facebook chief; Jack Dorsey, Twitter founder; and Sundar Pichai, head of Google, have all sided with Mr Cook.
Jack tries to exercise every day.
" The American has to top this,so he calls up one of his underlings and gives him the order: "Jack, Jump off the main mast into the ocean,and swim around the ship seventimes!
Jack Gerard, chief executive of the American Petroleum Association, which represents the industry, said: "The White House thinks Americans are not paying enough for gasoline, so they have proposed a new tax that could raise the cost of gasoline by 25 cents a gallon, harm consumers that are enjoying low energy prices, destroy American jobs and reverse America's emergence as a global energy leader.
