Date cutoff for results returned from API filing history

I’m using the Companies House API for the first time so apologies if this has been answered elsewhere. I wanted to check why carrying out an API call on a company number is returning a different set of results for filing history than using the CH online search. For instance, searching for Google (01161446) and filtering for Filing History → Incorporation, I have two results on the web tool (Incorporation & Memorandum and Articles of Association, both from 2000).

When I carry out a GET request and do a filing history search, I am able to find matching results for the most recent documents present, but in my results I am not able to find the two older incorporation documents in my search results. Is there a cutoff where older documents will not be returned through the API call?

Welcome - I’m slightly confused about this one - the number you give is for:

01161446 - Incorporated on 27 February 1974

Searching for “Google” shows various companies e.g.

Incorporated 2008

However using the advanced search to find only ones incorporated in 2000 I’m guessing you mean

03977902 - Incorporated on 20 April 2000

I’ve just used the API via curl to make the appropriate GET request and - limiting this just to the “incorporation” category - I get both expected results back e.g. the API gives me the same result as the web page:


(I've formatted the output and snipped some of the fields ("...") for conciseness.)

    "filing_history_status": "filing-history-available",
    "items_per_page": 25,
    "items": [
            "date": "2000-10-03",
            "type": "MEM/ARTS",
            "category": "incorporation",
            "description": "memorandum-articles",
            "date": "2000-04-20",
            "category": "incorporation",
            "type": "NEWINC",
            "description": "incorporation-company",
    "start_index": 0,
    "total_count": 2

What tool / language were you using for your GET? What parameters did you specify?