Oracle filed suit against Google in August, alleging that its Android mobile operating system infringes on seven of Oracle's Java patents. Google has denied any wrongdoing.
The subpoena, which was received by ASF on Monday, seeks "the production of documents related to the use of Apache Harmony code in the Android software platform, and the unsuccessful attempt by Apache to secure an acceptable licence to the Java SE Technology Compatibility Kit", the foundation said in a blog post.
ASF must produce the documents by 13 May, the post adds. "Apache will, of course, be complying with all court requirements. As an open development group the majority of our documents are already publicly available."
ASF's Harmony project is an open-source implementation of Java. The group had tried unsuccessfully to convince Oracle to lift restrictions on the Technology Compatibility Kit (TCK), which is used to cross-test Harmony against Java.
Tensions between ASF and Oracle resulted in ASF resigning from the Java SE/EE Executive Committee in December.
It's not clear how or if ASF will ultimately factor into the Oracle-Google matter.
The judge overseeing the case recently ordered both sides to reduce the number of claims each are making in an effort to streamline the case for the trial, which is set to begin later this year.