India-born Rajat Gupta had leaked boardroom secrets to Raj Rajaratnam, a former hedge fund manager who is serving 11 years in prison.
Gupta, 67, was released on Friday, the Press Trust of India said, quoting his record at Federal Bureau of Prisons.
The US court has agreed to re-hear his appeal against his 2012 conviction, reports say.
Gupta completed the last two months of his jail term at his home in Manhattan, after being released in January from a correctional facility.
He was confined to his apartment and was required to wear an ankle bracelet that monitored his movements, the Press Trust of India reports.
During the court case, which resulted in Gupta being found guilty in June 2012, the jury heard secret recordings of conversations between him and Rajaratnam.
The trial focused on a phone call made to Rajaratnam on 23 September 2008, minutes after Gupta had listened to a private conference call discussing a $5bn (Â£3.4bn) investment in Goldman Sachs by Warren Buffett's company Berkshire Hathaway.
The deal was due to be made public after stock markets closed that day.
According to phone records, Rajaratnam bought $40m in Goldman Sachs stock moments after the phone call, earning nearly $1m.
Apart from the two-year prison term, Gupta was also fined $5m.
Gupta, who was born in India and educated at Harvard, also served on the boards of Procter & Gamble, the Rockefeller Foundation and the Bill and Melinda Gates Foundation.

Khashayar Ghaharian called another member of staff a "cockroach" in his native Farsi, a Medical Practitioners Tribunal heard.
It also found he asked staff about their sex lives and made references to his sexual activities on holiday.
In total, 22 misconduct allegations against the Nottingham GP were proved.
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The retired physician, whose surgery closed despite protests from patients, now has 28 days to appeal.
The hearing considered allegations relating to a period between 2006 and 2012 at the Wollaton Vale Health Centre.
It heard Mr Ghaharian said he "hated" a doctor at another practice in the same building and said he hoped he died.
Another complaint included having called a receptionist "thick" and throwing prescriptions on the floor for her to pick up.
The tribunal report concluded: "It is clear that Dr Ghaharian's conduct has breached a number of the principles... and did not meet the standards expected of a registered medical practitioner.
"His unsavoury, bullying, harassing and deeply unpleasant conduct can readily be described as deplorable."
The report also noted the NHS had been forced to apologise to Mr Ghaharian after an investigation into alleged fictitious clinics.
It had been claimed that he had made up clinics on his computer in September 2012 in order to make it look like he had carried out work that he had not done.
However it still ruled against the former doctor in that he asked others to provide false statements to the investigation.

Hampshire can still qualify for the quarter-finals if results go their way in Wednesday's last group games.
Bailey struck an unbeaten 145 against Surrey on Sunday but in a losing cause.
"I don't think we've played a great game of one-day cricket yet, but we're breaking some records and the tide should turn at some stage," he said.
Bailey and Kyle Abbott (56) set a Hampshire List A record partnership for the eighth wicket of 152 against any county in the defeat by Surrey.
The game before, James Vince hit a county record 178 against Glamorgan, also in a losing cause.
If Hampshire beat Sussex at home and Surrey lose to Gloucestershire, they could finish in the top three of the South Group.
"I'm not sure we deserve to qualify," Bailey admitted to BBC Radio Solent. "But, that's the nature of the South Group where everyone seems to beat everyone.
"If we don't make it, we'll rue games like the one against Glamorgan (who chased 333 with a ball to spare).
"But if we play well against Sussex, you never know."
A former Goldman Sachs board member has been released after serving a two year sentence for insider trading in the US.
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A "deplorable" doctor has been struck off for calling his receptionist "the fat blob" and using expletives to describe patients.
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Hampshire captain George Bailey is unsure if his side deserve to qualify for the knockout stages of the One-Day Cup after inconsistent results.