OU D

Question

Dear Rav, What do they mean? From OU.org It is important to note that dairy ingredients or dairy residual material often are present in products at very low levels. According to halachah, a dairy component which is less than one part in sixty may be botel nullified. Nonetheless, as a matter of policy, the OU will not imply a product is pareve by printing an OU without a “D” on the label, even though the dairy component is at trace level.