Notably enough, the Cooper Clan is also one of the most honorable lineages of thieves; Coopers steal only from those undeserving of what they possess, due to underhanded dealings or more sinister arrangements. A pervasive code of honor binds each Cooper, as the general ethos of a Cooper heist is to deprive the real criminals – there is "no honor, no challenge, no fun in stealing from ordinary people." As Interpol Inspector Carmelita Fox put it, the Coopers and the police work towards the same goal on different sides of the law.
The Cooper Clan has often clashed with criminal organizations due to its honor code, including the Fiendish Five and the Klaww Gang. They have also bumped heads with rival thieves, such as Clockwerk or the Le Paradox Clan.
- Sly Cooper - The most modern master thief, Sly is the son of an honorable Cooper that went down fighting while protecting the Thievius Raccoonus. After the death of his parents, Sly was placed in an orphanage where he met his pals, Bentley and Murray, who he would later create their own Cooper Gang with. He defeated Clockwerk and Cyrille Le Paradox, two major enemies to the Cooper Clan. He also defeated Neyla, a corrupt Interpol agent who planned on becoming immortal, and Dr. M, a member of Sly's Fathers gang who attempted to steal the contents of the Cooper Vault.
Other major members
- Caveman "Bob" Cooper - The very first Cooper, "Bob" was a thief from 10,000 B.C. He stole Pteradactyl eggs as food for his tribe. His major contribution was the invention of the tool that became the very first Cooper Cane. His only special in game ability is being able to climb on icy surfaces since the common cooper techniques were not invented yet.
- Slytunkhamen Cooper I – He is the father of Slytunkhamen II and that he is the creator of "The Thievius Raccoonus".His signiture ability was to turn invisible to aid in stealing from corrupt Pharaohs and greedy noblemen.His special ability is known as "Shadow Power".
- Slytunkhamen Cooper II – Sly's ancestor from ancient Egypt circa 1300 BC, and creator of the Cooper Vault. He had two canes that bore a striking resemblance to the Egyptian Khopesh, He also was skilled at creating traps that were used in ancient Egyptian tombs.
- Salim al Kupar – Sly's ancestor from Arabia, circa 1001 AD, Salim is said to hold the stealth of 40 thieves. His weapon was a sword with a curved, hooked blade – sporting a scimitar-like look, but with a much thicker blade. Naturally, he wore a turban in his Cooper vault portrait. He has perfected a move called the Cobra Climb ability and owns a magic flying carpet.
- Sir Galleth Cooper - Sly's ancestor from the Medieval age, circa 1300 AD. He was an honorable knight and cunning thief who fought with a lance featuring a hook point. In this game it is shown that he perfected the wall hook climbing technique. He was also able to smash through barriers to get to his next point using the Catapult Crash.
- Slaigh MacCooper – Sly's ancestor from Scotland. The strongest of all of the Coopers, he could break any lock with a single blow using his large stone cane. He was the Cooper who created the wall-edge sneak.
- Rioichi Cooper – Sly's ninja ancestor from Feudal Japan, circa 1600 AD. He created the Ninja Spire Jump and implemented Japanese artwork of himself in his part of the vault. His weapons were two small canes, resembling hooked sais. He used the Spire Jump to sneak into heavily fortified castles in Japan.
- Henriette "One Eye" Cooper – A woman who sailed the seas circa 1616 AD and stole from other pirates. She had the innate ability to smell gold. Originally wielding a hooked dagger, she lost a hand and replaced it with a hook shaped like that of the trademark Cooper cane.
- "Tennessee Kid" Cooper – Sly's outlaw ancestor from the nineteenth century Western United States, circa 1884. He carried a six-shot revolver with a hooked handle. Tennessee Kid also invented the rail walk and rail slide. He used these to his advantage, due to the fact that there were many train rails all over the land.
- Thaddeus Winslow Cooper III - A Cooper from Victorian-era London, circa 1893, who was the most "gentlemanly" thief and a master of disguise. He had a cane similar to Sly's; the only difference is a red ruby-like gem at the end of its hook. It was his charm that was used by Sly to fool Carmelita in the theft of a rare chocolate bar.
- Otto Van Cooper – An ancestor of Sly's from Germany who was a genius mechanic and skilled fighter pilot, much like Penelope. Due to his physical ineptitude, he used his talent to pull off heists with his machines facilitating his thievery. He kept some of his technical blueprints in the Thievius Raccoonus. The propeller blades of his biplane were shaped like the trademark Cooper hook.
- Conner Cooper – He used the same cane that now belongs to Sly. Before being killed by the Fiendish Five, he pulled heists with McSweeny and Dr. M, and created a technique to slide along lasers. He is seen as nothing more than a silhouette throughout the series. He did not write his "Laser Slide" move in the Thievius Raccoonus; rather, Sly learned the move while in the Cooper Vault.
- Drake Cooper – He created the Knockout Dive. The main use of this is spinning the cane while lunging forward. He later developed it to use as a drop dive. This move is also available as an unlockable power-up in Sly 2: Band of Thieves, and as a purchasable power-up in Sly 3: Honor Among Thieves.
- Sally Cooper – Sally Cooper was a female member of the Cooper Clan. She created a locomotion move, the Roll, which is only available for Sly in Sly 1. Later it was upgraded by Kelle McCooper so that it could project an electric field around the user.
- Dev Cooperinda – The creator of the Slow Motion Jumps. This move is dubbed "Slow" in Sly Cooper and the Thievius Raccoonus, and "Thief Reflexes" in Sly 2: Band of Thieves and Sly 3: Honor Among Thieves.
- Chris Cooper – Born Christopher Cooper, he invented the coin-collecting dive technique. The move comes standard in both sequels, however it no longer collects coins as it makes its impact, rather relying on its brute force to daze or stun enemies.
- Karin Coopergiwa - She invented the coin magnetism technique. Her magnet had been stolen from Rioichi by El Jefe and placed in a safe. This means Karin was around prior to Rioichi. The name "Karin Coopergiwa" is a reference to the name of Karin Yamagiwa, who is one of the level designers in the Sly series. This information is featured in "The Making of Sly 2" movie. The movie can be viewed by highlighting Episode 7 on the Sly 2 episode menu and using the police badge easter egg.
- Rob McCooper – One of the various members within the Cooper family lineage and is directly responsible for the creation of the Mine technique. Not much is known about Rob McCooper, though it is implied that he had developed a strong love for stealing hats, which eventually lead to him perfecting the Mine technique. He is named for Rob McDaniel, who can be seen in the credits for Sly Cooper and The Thievius Raccoonus.
- B.F. Cooper – A male member of the Cooper Clan. The inventor of the Fast Time technique and Sly's hyperactive ancestor, he developed a technique that not only allowed security to go faster but himself in addition. He could be described as the opposite persona of Dev Cooperinda. Bentley said that he might have used it to speed up long stakeouts.
- Suzanne Cooper – Suzanne Cooper was a female member of the Cooper Clan. She had a strong aversion to water, and to counter this designed and documented a move that allowed her to jump out of it without losing a lucky charm. Sly used the move to his own advantage during his battles against the Fiendish Five.
- Sir Andrew Cooper – He created the thief replica, or "Decoy" technique. This allowed one to distract guards, giving you the chance to slip past them. This trick is only used in in Sly Cooper and the Thievius Raccoonus.
- Kelle McCooper – Kelle McCooper was a male member of the Cooper Gang who discovered how to harness the electromagnetic field created by rolling, and augmented Sally Cooper's rolling technique with an electrical aura.
- Bruce O'Coop – An ancestor of Sly's who was an expert hacker. Bruce O'Coop was a male member of the Cooper Clan, and was known as the smartest of all Coopers.
- Matthew de la Coopeur – He was French and the slowest Cooper, creating the perpetual slow motion technique. This is available in all of the Sly games, but renamed "Thief Reflexes" in Sly 2 and Sly 3, Bentley wonders if he was influenced by the Thief Costumes ability to slow time.
- Huckleberry Cooper – Taking after the famous fictional Huckleberry Finn, he was the inventor of the ability to move (slowly) while invisible. The technique itself is available in all of the Sly Cooper games.
- Colonel Reid Cooper – Colonel Reid was the inventor of the time stop move (the final ability in Sly Cooper and the Thievius Raccoonus). The freeze move is in the first game and works on all guards including bosses.
- Augustine Cooper – Augustine Cooper was the inventor of the ability to briefly defy gravity. It is an incredible power that will let Sly fall in bottomless pits without losing a horseshoe. It is even said that Augustine could levitate for days on end and not even break a sweat; while at it he could rob anyone he chose blind, and they wouldn't even know where he went because of the lack of tracks. This move also proves helpful when accidentally falling off of large edges and cliffs.
- Slytunkhamen Cooper III – He appears in the opening cutscene of Sly Cooper and the Thievius Raccoonus and is shown stealing from pharaohs, much like his father and grandfather. His cane is very similar to Sly's Cane.
- Thaddeus Winslow Cooper I – He is the Grandfather of Thaddeus Winslow III. He is never mentioned in the series.
- Thaddeus Winslow Cooper II – He is the father of Thaddeus Winslow Cooper III. He is never mentioned in the series.
- Sly's Mother – His mother is never mentioned, and is unnamed but she is seen in a picture with Sly's dad and Sly with some balloons in his hand, she is cutoff in the picture at the waist. When Sly remembered his father fighting the Fiendish Five in their home, he stated that he "fought to protect us".
The Thievius Raccoonus is an ancient book, in which every Cooper Clan member since Ancient Egypt has recorded their thieving escapades, in addition to instructions on their various moves. It was created by Slytunkhamen Cooper and was then passed down through the family for generations, but was later stolen and divided among the Fiendish Five on the day Sly was to inherit the book. After 10 years, Sly tracked down the criminals and recovered the Thievius Raccoonus, afterwards recording his own adventures in the great book. After Sly left the life of a thief behind to strike up a relationship with Carmelita Fox in Sly 3, the book fell into the care of Bentley, who became the first non-Cooper in history to write in the Thievius Raccoonus.
The Cooper Clan Vault is located on the fictional Kaine Island and is the main target in the game Sly 3: Honor Among Thieves . It is home to all of the member's treasure and their unused weapons.
The vault's only entrance is an unbreakable door, which can only be unlocked by the Cooper cane (hence the name of the island). In Sly 3, Dr. M, the main antagonist, unsuccessfully tries to steal the treasures by breaking open the vault using machine force and by trying to forge the Cooper family Cane. After many more unsuccessful attempts, he grows paranoid and constructs a heavily-guarded fort on it. After recruiting a team of specialist thieves, the Cooper Gang penetrates the defenses around the island and enters the vault. Inside, Sly Cooper and Carmelita Fox defeat Dr. M, which causes the vault to cave in, killing Dr. M and seemingly giving Sly amnesia (he actually fakes it to grow closer to Carmelita Fox and start a relationship with her). The Cooper Vault was restored to its former glory when Bentley and Penelope rebuilt it, with upgraded security and the additions of Bentley and Murray's sections.