Keep the following limits in mind when setting up your inventory and orders:
Neither key-values or ad units are case-sensitive.
Pre-defined values per key: 200 (Learn more about pre-defined key-values)
Default maximum number of keys: 20. If you would like to increase this limit, contact your technical account manager.
Default maximum number of values per key: 200. If you would like to increase this limit, contact your technical account manager.
Maximum number of reportable key-values per network: 50,000 (e.g. 1 key with 50,000 values would reach the limit, or 100 keys with 500 values would reach the limit).
Default maximum characters per custom targeting key: 10.
Default maximum characters per custom targeting value: 40.
Number key-values a line item can target: No hard limit.
Limit to the number of key-value characters you can include in an ad tag: 2,000.
Maximum number of boolean AND relationships per line item: 8 (you can have 7 ANDs).
Ad unit names can be up to 100 characters in length and must be unique. You can only include alphanumeric characters, periods, hyphens, and underscores (no spaces or slashes).
URL length limit: 2,083.
Number of orders, line items, creatives, ad units, placements, and advertisers
DoubleClick for Publishers systematically monitors the creation of orders, line items, creatives, ad units, placements and advertisers. If we detect that your network is unintentionally creating excessive objects (for instance, if someone is inadvertently calling the API to create hundreds of thousands of ad units per day), we may temporarily limit the creation of new objects to protect your network from performance and stability issues.