If you submit AdWords API exemption requests for policy violations, then you may need to modify your application as a result of these recently announced policy changes.

What is changing?
For some policy violations, the values of the externalPolicyName, externalPolicyUrl, and externalPolicyDescription fields on PolicyViolationError will change.

What is not changing?
The policyName field value on PolicyViolationError.key will not change.

Could you remind me what a PolicyViolationError looks like?
Absolutely - glad you asked! In the following sample, after the policy changes go live, the content in externalPolicyName, externalPolicyUrl, and externalPolicyDescription may change, but the policyName field will stay the same. 
<errors xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:type="PolicyViolationError">
  <fieldPath>operations[0].operand.ad.headline</fieldPath>
  <trigger/>
  <errorString>AdPolicyError.POLICY_ERROR</errorString>
  <ApiError.Type>PolicyViolationError</ApiError.Type>
  <key>
    <policyName>nonstandard_punctuation</policyName>
    <violatingText>!!!</violatingText>
  </key>
  <externalPolicyName>Non-standard punctuation</externalPolicyName>
  <externalPolicyUrl/>...</externalPolicyUrl>
  <externalPolicyDescription>Google ads aren't allowed to have excessive or unnecessary punctuation or symbols such as the following:
    ...
    &lt;a href="https://support.google.com/adwordspolicy/answer/176095" target="_blank"&gt;See the full policy&lt;/a&gt;
  </externalPolicyDescription>
  <isExemptable>true</isExemptable>
  <violatingParts>
    <index>18</index>
    <length>3</length>
  </violatingParts>
</errors>
What should you do?
If your application looks for specific values of externalPolicyName, externalPolicyUrl, or externalPolicyDescription to decide if a failed AdGroupAdOperation should be resubmitted with one or more ExemptionRequests, please make the following changes:
  1. Modify your application to use the policyName instead of one of the externalPolicy fields. The values for policyName are non-localized constants, so this is a more reliable field for this use case.
  2. In early June, 2016, monitor your logs for occurrences of PolicyViolationError. Look for any new policyName values that you may want to incorporate into your application's logic for submitting exemption requests.
If you have any questions or need help, please post on the forum or the Ads Developers Plus Page.

- Josh Radcliff, AdWords API Team