OBC - Orange Book Code
 OBC3 information and code values 
 OBC3 - Orange Book Code; 3-Byte Version
  A three-character alphanumeric column that identifies the equivalency ratings assigned to approved prescription products according to the FDA’s Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book). The source is First Databank.

In certain instances, the FDA adds a number to the end of the AB code to make a three character code (i.e., AB1, AB2, AB3, etc.). These three-character codes are assigned only in situations when more than one reference listed drug of the same strength has been designated under the same heading. Two or more reference listed drugs are generally selected only when there are at least two potential reference drug products which are not bioequivalent to each other. If a study is submitted that demonstrates bioequivalence to a specific listed drug product, the generic product will be given the same three-character code as the reference listed drug it was compared against. For example, Nitro-Dur and Minitran are listed as AB1. Transderm-Nitro and Mylan’s patch are listed as AB2. Drugs coded with an OBC3 are considered therapeutically equivalent only to other drugs coded with the same OBC3 under that heading. Refer to the Orange Book for more information on the three-byte Orange Book Codes.

At present, McKesson Connect displays a single OBC3 assignment per NDC. In the rare situations where multiple OBC3 values for a given NDC exist, a representative OBC3 is chosen and assigned in the data.

When there is not a three-byte code in the Orange Book, the default OBC3 will be the two-byte OBC plus a trailing blank.

VALID ORANGE BOOK (2- and 3-character) VALUES TABLE — Therapeutic Equivalence Acceptable Codes
obc obc_desc
AA Products with no known bioequivalence problems in conventional dosage forms.
AB, AB1,
AB2, AB3
Products meeting necessary bioequivalence requirements.
AN Solutions and powders for aerosolization that are marketed for use in any of several delivery systems. Drugs that are marketed for only a single delivery system or are a component of a specific delivery system are not included.
AO Injectable oils with identical active ingredients, concentration, and type of oil.
AP Injectable aqueous solutions including dry powders, concentrated solutions, or ready-to-use solutions are considered pharmaceutically and therapeutically equivalent if they produce the same concentration and are labeled similarly.
AT Topical products therapeutically equivalent in same dosage form.
VALID VALUES TABLE — Not Equivalent Codes
B Products with A or B codes previously assigned; new information raised significant questions which require further FDA investigation and review to determine therapeutic equivalence.
BC Controlled-release tablets, controlled-release capsules, and controlled-release injectables unless specifically proven to be equivalent.
BD Active ingredients and dosage forms with documented bioequivalence problems.
BE Enteric coated dosage forms unless proven otherwise to be equivalent.
BN Products in aerosol-nebulizer drug delivery systems that are marketed as a component of or specifically for a particular delivery system.
BP Active ingredients and dosage forms with potential bioequivalence problems.
BR Suppositories or enemas for systemic use unless proven to be equivalent.
BS Products having drug standard deficiencies
BT Topical products with bioequivalence problems.
BX Insufficient data to determine therapeutic equivalence.
VALID VALUES TABLE — Intermediate Equivalency Codes
ZA Particular pharmaceutical entity (GCN) looked at but particular labeler was not evaluated.
ZB Particular pharmaceutical entity was not evaluated.
ZC Pharmaceutical entity and labeler evaluated but no therapeutic equivalence rating given. Usually applies to single source drugs.