To query patents by the number of unique assignment events associated with a patent, use the ANA_ANRE_EXE_CT field code.

Patents with lots of assignment events are sometimes difficult to unwind when trying to clear the title before a transaction takes place. The ANA_ANRE_EXE_CT analysis field helps you determine which patents may require additional work to clear title.

It is not used very often, but it is a handy measure of the potential complexity of a transaction.

To double check you have inventor releases in place, you can query the field by querying for patents where the field is empty:

FIELD:isEmptyANA_ANRE_EXE_CT

If you want to find patents with long or short claim one (1), use the ANA_FCLM_TW field code.

Length of claim one is one of the most important and useful value indicators.  Patents with short claims tend to have far fewer limitations than patents with long, rambling claims.  From talking to many ex patent examiners, short claims are particularly scrutinized for fear that the claim may be overly broad.

For sake of comparison, in 2013 the median length of claim 1 was 156 words.  

Helpful Hint:

Whenever I have to do a claims level review of patents, I first create my queries and isolate the patents that I want to read.  THEN I sort by claim one, "Claim One (Total Words)" with the shortest claims on top.  The reason I do this is to acclimate my brain to the language around the technology from fairly simple claims before I dive into the longer ones.  I do better work every time if I first sort by the length of claim one.

Also Note:

Many published applications have very short claim 1's.  The word is "Cancelled."  So this value indicator is much easier to use when reviewing granted patents.

The pendency is the amount of time between the file date of a patent and the grant date.  To query patents by their pendency use the ANA_PEND field code.

For un-granted applications the pendency is the number of days that have elapsed since the patent was filed.  Once an application "grants" the pendency remains fixed.  AcclaimIP re-computes the pendency field every week.

Pendency is an important value indicator with a unique value profile.  The median pendency is 1126 days or about 3.1 years.  As pendency increases, the average length of claim one also increases suggesting that a long pendency narrows the patent as the applicant responds to rejections from the patent office.  If you've prosecuted patents, then you will not find this surprising.

However, as pendency gets very long, it is an indicator of interference proceedings, and is often NOT indicative of rejections and further narrowing of the scope of the claims.  Therefore, patents with very very long pendencies tend to be some of the most valuable patents.

In the figure below, the ANA_PEND field measures the Pendency Gap.

To query documents by the number of reverse citations, use the ANA_REFCITE_CT field.

Reverse citations are older documents that a patent cites. Reverse citations are published along with the issued patent, and they do not change or increment as time goes on.  In other words, the reverse citations remain fixed during the life of the patent.

To query patents by the total number of claims, use the ANA_CLM_CT field.

Claim count is a value indicator especially since new rules whet into effect requiring additional examination fees if a patent contains more than 20 total claims and/or 3 independent claims.  Here is an interesting (although a little outdated) article on the topic:

http://patentlyo.com/patent/2007/08/patents-with-mo.html

By contrast to the 2007 data in the Patentlyo article, of the 5820 utility patents granted on 02/18/2014, only 9.9 percent had more than 25 claims--a drop of almost 50%!