The only matches 24-year-old left-back Wood did not start in 2020-21 were in the Football League Trophy, and he leaves one match short of 100 league starts for the club.
The only league game O'Connor missed last season was at home to Stevenage in September. He was serving a one-match suspension for a red card at Forest Green.
The 28-year-old showed his versatility throughout the campaign, playing in central defensive twos and threes, at right-back and as a holding midfielder.
Novak, signed from Scunthorpe United in January 2020, took over the captain's armband when Richard O'Donnell was injured in December but picked up an injury himself shortly after scoring an outstanding goal at Grimsby Town. He missed the whole of the first four months of 2021 with a knee injury that was expected to rule him out for four to six weeks.
Chief executive Ryan Sparks spoke this week about the need to improve the club's injury record.
Billy Clarke and Harry Pritchard have also been released after being dogged by injury problems.
The Bantams were only able to get 20 League Two starts out of talented 33-year-old attacking midfielder Clarke in his only season at Valley Parade, and only one of Pritchard's 21 outings came after the turn of the year.
The much-travelled Donaldson, now 37, will also leave. Towards the end of Stuart McCall's time as manager, he had to carry the burden of often being the club's only fit centre-forward in an extremely physically-demanding campaign and although he featured very little in the early days of Mark Trueman and Conor Sellars, with Novak back to full fitness, he had a strong April, often used as a No 10.
Amongst the Jamaican's many former clubs are Hull City, Harrogate Town, Scarborough, Halifax Town, York City and Sheffield United.
Zeli Ismael, Connor Shanks and Will Huffer, signed as goalkeeping cover in January, have also bee released after one League Two start between them this season.
Pritchard, Huffer and Ismael will continue to receive treatment from Bradford's medical team in their rehabilitations.
Loanees Andy Cook, Jordan Stevens and Rumarn Burrell have returned to their parent clubs. Trueman and Sellars made it clear they wanted to keep Cooke permanently, but that decision will now fall to a new manager after they were dismissed this week.
Jorge Sikora, Kian Scales, Matty Foulds and Sam Hornby have been offered new contracts.
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