In keeping with other, better, “ask” services: entanglement omnibus! So far, the record for the largest number of “maximally entangled” particles is 14 (“Maximally entangled” means “perfect correlation”). Entanglement can take a lot of forms, but one example state of perfect 14 particle entanglement would be something like: . This weird transference of entanglement (where the entanglement between two particles causes other things to become entangled) is essentially how quantum teleportation works. So, if anyone intercepts either entangled photon before it gets to where it’s going, the entanglement is broken (remember: entanglement means correlation and multiple states).