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A prime filter of a distributive lattice $P$ is a proper lattice filter: it contains the top element, is upward closed, and is closed under finite meets. Primality means

The Priestley dual space $\hat{L}$ of a distributive lattice $L$ has all prime filters of $L$ as its points. Its order is inclusion. For each $a\in L$, putThe topology is generated by the sets $a^{\ast }$ and their complements. Each $a^{\ast }$ is therefore a clopen up-set, and these sets separate points and order. With this topology and order, $\hat{L}$ is a compact totally order-disconnected ordered space.

The Stone prime filter theorem says that if a lattice filter $F$ and a lattice ideal $I$ of a distributive lattice are disjoint, then there is a prime filter of a distributive lattice $P$ such thatEquivalently, whenever $a\nleqq b$, there is a prime filter containing $a$ and omitting $b$.

The Priestley dual space $\hat{L}$ of a bounded distributive lattice $L$ consists of its prime filters, ordered by inclusion and topologized by the sets $a^{\ast }=\{P:a\in P\}$ and their complements.

This construction yields a Priestley space: a compact ordered topological space in which suitable clopen upward-closed sets separate distinct comparable-order failures.

A proper lattice ideal $I$ is prime if $x\wedge y\in I$ implies $x\in I$ or $y\in I$. Its complement is a prime filter of a distributive lattice when the lattice is distributive: downward closure of the ideal makes the complement upward closed, primeness makes it meet-closed, and join closure makes that filter prime. Equivalently, its complement indicator is a homomorphism of lattices to the two-element lattice. Given $b\nleqq a$ in a distributive lattice, maximize an ideal containing $a$ and avoiding $b$ using Zorn lemma. If $x,y$ lie outside it, the two enlarged ideals contain $b$, so $b\le i\vee x$ and $b\le j\vee y$ for some $i,j\in I$. Distributivity shows that $x\wedge y\in I$ would force $b\in I$, a contradiction. Thus this maximal avoiding ideal is prime and separates the two specified elements.

If a lattice filter $F$ and lattice ideal $I$ in a distributive lattice are disjoint, there is a prime filter of a distributive lattice containing $F$ and disjoint from $I$.

The Boolean prime ideal theorem is the Boolean-algebra version; distributivity gives this corresponding filter-extension statement.