# How does P4O10 make sense? [duplicate]

I'm trying to understand the gains phosphorus has from forming $\ce{P4O10}$. The molecular structure is such that every oxygen atom forms two bonds (either two with one phosphorus atom, or one with two), while every phosphorus atom forms five bonds.

I'm clear about the gains the oxygen has from this -- it fills its outer shell to the octet rule, mimicking neon effectively. But what about phosphorus? We're talking about a covalent bond, so forming five bonds would leave it with five extra electrons, which is two more than it needs to reach an optimal configuration.

I remember reading somewhere (possibly on this site) that ionic bonds can be regarded as an extreme form of covalent bonds, where the difference in electronegativity is so great, that the metal gives its extra electrons to the non-metal. Can we assume that the difference in this case is also large enough, such that phosphorus effectively 'gives' away five electrons, therefore reaching neon too? Or am I oversimplifying it?