What follows is an opinion from a United States Court of Appeals.
Intervenors who participated as parties at the courts of appeals should be counted as either appellants or respondents when it can be determined whose position they supported. For example, if there were two plaintiffs who lost in district court, appealed, and were joined by four intervenors who also asked the court of appeals to reverse the district court, the number of appellants should be coded as six.
When coding the detailed nature of participants, use your personal knowledge about the participants, if you are completely confident of the accuracy of your knowledge, even if the specific information is not in the opinion. For example, if "IBM" is listed as the appellant it could be classified as "clearly national or international in scope" even if the opinion did not indicate the scope of the business. 

Your task concerns the first listed appellant. The nature of this litigant falls into the category "private business (including criminal enterprises)". Your task is to determine what category of business best describes the area of activity of this litigant which is involved in this case.

Opinion:
DIRECTOPLATE CORPORATION v. DONALDSON LITHOGRAPHING CO.
No. 5630.
Circuit Court of Appeals, Sixth Circuit.
Oct. 9, 1931.
Before MOORMAN, HICKS, and HIGKENLOOPER, Circuit Judges.
PER CURIAM.
Upon petition for rehearing it is insisted that the court misread the drawings in evidence and erred in holding that, in defendant’s device, “the negative is carried by clamps upon the inner and under portion of the outer frame and the inner frame is used solely for the purpose of hermetically sealing the negative within the outer frame.” 51 F.(2d) 199, 201. A model of defendant’s frame is now presented, and from this it appears that the court did make the error suggested. It follows that the portion of the opinion above quoted should he modified to conform to the fact, which is, that the negative is carried by clamps upon the inner frame to which it is hermetically sealed by pressure and a rubber strip; and the inner frame is then firmly attached tó the outer frame, before use, by pairs of set screws, the opening between the inner and outer frames being sealed by a vertical curtain of flexible rubber cloth.
The foregoing correction in no way requires a different conclusion than that heretofore reached. The two frames of the defendant’s device must still be considered as operatively and functionally integral, and the manner of operation of the device as substantially different from that of the patent (Koppe, No. 1,396,962).
The petition for a rehearing is denied.

Question: This question concerns the first listed appellant. The nature of this litigant falls into the category "private business (including criminal enterprises)". What category of business best describes the area of activity of this litigant which is involved in this case?

Choices:
agriculture
mining
construction
manufacturing
transportation
trade
financial institution
utilities
other
unclear

Answer: 3