- She claims that she was diagnosed with cancer in 1997, which took her arm. However, in Walter's recollection of 1985, she damaged her arm when she reached through the portal to the alternate universe to try and stop Walter from kidnapping Peter. At some point after that she lost her arm and had it replaced with a robotic arm designed by William Bell and Massive Dynamic. She was shot in the chest (The Road Not Taken) and robbed of the powerful energy cell hidden in her robotic arm. She has Kevlar components (There's More Than One Of Everything) in the sternum region of her chest that helped her survive being shot. Technicians from Massive Dynamic returned function to her arm when she was in the hospital recovering from the gunshot wound to her chest. She attributes Sam Weiss with helping her recover (Night Of Desirable Objects) from the loss, and replacement, of her arm.
- In The Cure, Nina told Peter Bishop that she knew him when he was a small boy, that she and his father, Walter, were once quite close and that she and Peter spent time together at the equestrian center where they were sitting.
- In A New Day In The Old Town, a deeper aspect of Nina's and Broyles' personal relationship comes to light when she kisses him passionately on the steps of the United States Capitol. Broyles seems to neither respond to, nor reject, the approach.
- In Brown Betty, Walter depicted in his fictional tale to Ella that Nina Sharp had a relationship with William Bell.
- In Peter, in 1985 she characterized as a close associate of Walter, William Bell and Carla Warren. She is shown to have knowledge of their research on the alternate universe, and the potential effects of crossing from one universe to the other. When she attempts to stop Walter from traversing the soft spot at Reiden Lake, her arm is molecularly damaged when power to the portal is interrupted.
- In The Box, during the reading of William Bell's will by the executor of his estate, she receives a ship's bell as a memento of time they spent in Tuscany.
- In 6955 kHz, she locates, and shares with the science team, one of the clandestine radio transmissions that Massive Dynamic intercepted four years earlier. It was in Spanish, and as far as she knows, it never induced or triggered amnesiatic responses.
- In Subject 9, she grants Olivia and Astrid access to the archived Cortexiphan records maintained at Massive Dynamic, then takes Olivia aside for a little maternal advice and TLC.
- In Novation, she briefs Agent Lee and Olivia on former employee Malcolm Truss and the biotech project he ran for William Bell. She travels to Walter's to lab to make amends over their bitter history since Reiden Lake, and to encourage Walter to help Peter with his quest to return to his own timeline.
- In Wallflower, she briefs Olivia and Agent Lee about experimentation conducted on the young, photo-adaptive Eugene.
- In A Better Human Being, she is confronted about the supply of decades old Cortexiphan she has in secure storage. She leads Agent Lee and Walter to the remaining samples from the original trials.
- In The End Of All Things, she is formally questioned by Fringe Chief Phillip Broyles about the abduction of Olivia and the missing Cortexiphan.
- In A Short Story About Love, she and Olivia have breakfast and chat about the memories she's experiencing.
- In Nothing As It Seems, she briefs Olivia and Peter on the experiments conducted by David Robert Jones.
- In Letters Of Transit, in 2036, she provides Simon and Henrietta the means to regenerate the portions of Walter's brain he had removed.
- In Brave New World, Part 1, she meets with Walter and Olivia at Liberty Island and discloses Bell's cancerous prognosis and planned demise.
- In Brave New World, Part 2, she works with the team in Walter's lab to reanimate Jessica Holt, then locates and accompanies Olivia and Peter to Bell's cargo vessel in the Atlantic.
- In Five-Twenty-Ten, in 2036, she reunites with the science team and provides them with the gear they need to recover two Beacons stored under the collapsed Kelvin Genetics complex.
- In Black Blotter, in 2036, she appears as one of two muses in Walter's LSD induce hallucinations as he works through his personal ethics issues.
- In Anomaly XB-6783746, in 2036, she leads the fugitive science team to a secret underground lab to recover equipment to communicate with the Observer progeny. When trapped, she takes her own life rather than convey the whereabouts of the child or the science team.
- Nina has referred to herself as "Executive Director" of Massive Dynamic, a common nickname for her official title - Chief Operating Officer (COO).
- SEMI-CANON→ In her years with the company, Nina Sharp has overseen the firm's rise from feisty upstart - to multinational conglomerate. As Senior Vice President of R&D, Nina demonstrated her skill in transforming concept into product. Since her 2004 promotion to Chief Operating Officer, Nina has spearheaded the firm's entry into entertainment, education, and environmental management. In 2007, she headed The Women's Progress Foundation's annual list of the Top 10 Women in Business. ←SEMI-CANON