A hotshot trader just quit Goldman Sachs to join its arch rival

A young hotshot trader just quit Goldman Sachs.

Kerri Saperstein, who works in high-yield bond trading, has left the bank, according to people familiar with the matter. She is moving to take a similar role at Morgan Stanley, according to people familiar with the matter.

Saperstein was named on Forbes' 30 under 30 list this year, where she was reported to be a bond trader running one of Goldman Sachs' five high-yield market-making books.

Saperstein holds a bachelor's degree from the University of Pennsylvania, according to a wedding announcement in The New York Times. She joined Goldman Sachs in 2010.

Morgan Stanley reported earnings of $1 a share on revenue of $9.7 billion in the first three months of 2017 on Wednesday, beating analyst estimates by a lot. That performance was driven by a big rebound in fixed-income sales and trading revenue. Morgan Stanley reported fixed-income revenue of $1.7 billion, up from $873 million.

That performance is especially impressive, given Morgan Stanley slashed the size of its fixed-income unit in late 2015. The bank has managed to cut costs and staff while boosting revenues.

It also means that Morgan Stanley's first quarter fixed income revenues ($1.714 billion) were ahead of Goldman Sachs' fixed income revenues ($1.685 billion). The fixed income performance had Wall Street analysts digging for more information on how Morgan Stanley has pulled it off.

"We've been very pleased with the performance in that business," Morgan Stanley CFO Jonathan Pruzan said on a call. We're generating "significantly more revenues than before we had that restructuring," he said. "Our market share and momentum in that business has been good ... We feel confident that we will continue to be relevant to our clients."

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