Match ISS Voting Analytics with CRSP Mutual Funds

Here is a summary of the procedure, built on Peter Iliev's note, for matching mutual funds between ISS Voting Analytics and CRSP databases.

In Appendix B of Sulaeman and Ye (2023), we perform the following procedure to link ISS mutual funds (FundID) with CRSP mutual funds (CRSP_PORTNO).

As described in Peter Iliev’s note, each proxy voting record in the ISS data can be linked to the original SEC Form N-PX using the reference identifier (NPXFileID). From the SEC’s N-PX file, we obtain a list of fund class tickers (TICKER) associated with the registered management investment company on the filing date. Because the CRSP Mutual Fund Summary data provide a direct linkage between the fund class tickers (TICKER) and the fund portfolio identifiers (CRSP_PORTNO), we are able to map FundID from ISS to CRSP_PORTNO from CRSP by TICKER in each quarter.

We observe that, in most cases (88% in our exercise), a FundID in a quarter is matched with multiple CRSP_PORTNOs, because a N-PX file typically refers to multiple funds under the same investment management company. For each FundID, we identify the most probable CRSP_PORTNO via matching the fund name between the two databases, using both Jaro-Winkler and Levenshtein Distance name-matching algorithms. We retain the pairs of FundID-CRSP_PORTNO with the minimum name distance according to the two algorithms and further require the distance to be less than 0.3 for Jaro-Winkler and 10 for Levenshtein Distance. In about 72% of the FundID-CRSP_PORTNO pairs, Jaro-Winkler or Levenshtein Distance reports a perfect match between the ISS and the CRSP fund names. For the remaining 28% of the cases where fund names are not exactly matched, we manually verify the accuracy of the mappings. As our name-matching methodology tightens the links between FundID and CRSP_PORTNO within an investment management company in a quarter, it performs better than a general, unconditional matching using a universe of fund names from the two databases.

Suggested citation: Sulaeman, J. and Ye, Q.(2023). Who do you vote for? Same-race voting preferences in director elections. European Corporate Governance Institute – Finance Working Paper No. 872/2023