The extra award dished out in July was the most significant change in Dimon's annual pay, which faces a non-binding vote at the bank's online annual meeting.
While say-on-pay votes are only advisory and Dimon, 66, is expected to keep the award regardless, they are closely followed as a test of investors' attitudes toward executive pay, which have hardened in recent years.
Average support for pay packages at S&P 500 companies was 88.3% in 2021, down from 89.6% in 2020 and 90% in 2019, according to consulting firm Semler Brossy.
JPMorgan has won approval from more than 90% of votes cast in its annual compensation ballots in eight of the last 12 years.
But this year two major advisory firms, from which investors take their cue when voting, have recommended that they vote "no" because of the special award.
The last time both Institutional Shareholder Services Inc and Glass Lewis & Co objected was in 2015. Then, only 62% of votes were cast for JPMorgan's payouts, according to data firm Insightia.
This year, the firms have criticized Dimon's new options as lacking performance requirements for vesting.
JPMorgan directors have said that Dimon's special award "reflects the board's desire for him to continue to lead the firm for a further significant number of years."
If Dimon, a billionaire, keeps working at the bank for five years the options will vest, although he could still receive them if he leaves to work for the government or to run for public office.
Stock from the options must be held until 10 years after being granted.
The board said it considered Dimon's performance, his leadership since 2005 and "management succession planning amidst a highly competitive landscape for executive leadership talent."
The award was separate from Dimon's usual annual pay package, which was up 10% to $34.5 million for 2021.
America's too-big-to-fail banks are following other companies with retention awards to keep their leaders from being lured away by competitors, according to Glass Lewis.
"The result has been another ratcheting up of CEO pay," Glass Lewis wrote to clients about the upcoming JPMorgan vote.
Goldman Sachs Group Inc also gave some of its top executives special awards last year, including one to CEO David Solomon worth $17 million.
ISS endorsed Goldman's compensation after concluding that Solomon's special award is "entirely performance-based" and carries "rigorous" goals for shareholder returns. Last month, 82% of votes cast backed the pay.
Glass Lewis recommended voting against Goldman's compensation, citing the "excessive sizes" of the awards.
In December, JPMorgan directors also gave a special $27.9 million stock option grant to Daniel Pinto, the bank's chief operating officer.
JPMorgan's board described the special awards as "one-time" and that they would not be made on a "regularly recurring basis."
(Editing by Michelle Price and Nick Zieminski)
By David Henry and Ross Kerber