Certificate Files, September 27, 1906 - March 31, 1956

Background

C-Files are a product of the Basic Naturalization Act of 1906, which created the Federal Naturalization Service and required the new agency to collect and maintain duplicate copies of all court naturalization records.  Initially, courts forwarded copies of Declarations of Intention, Petitions for Naturalization, and naturalization certificates to Washington, D.C.  Later, Congress expanded the Naturalization Service authority to create additional C-Files relating to derivative and resumed U.S. citizenship, as well as repatriation.

The Files Today

C-Files dated 1906 to ca. 1944 (C-1 to C-6500000) were microfilmed in the 1950’s.  Sadly, the original files were destroyed.  The only C-files below C-6500000 remaining in paper form are those that were 1) unavailable at the time of filming or 2) re-opened after microfilming for further action.  Immigrants with C-Files below C-6500000 may have additional USCIS files depending on their arrival date or naturalization date.  Some C-Files below C-6500000 are Consolidated C-Files and are the only file for that individual.

C-Files C-6500000 to approximately C-7700000 (to March 31, 1956) are considered “Consolidated C-Files” containing all agency records on that individual subject.

Research Value

Since 1906 standard naturalization forms called for the immigrant’s name, date and place of birth, and port and date of arrival.  When applicants claimed arrival after June 30, 1906, the Naturalization Service verified the arrival information by checking the original immigration record.

Despite the standardization mandated by the 1906 naturalization law, standard C-Files do vary by date and the circumstances of the naturalization.  The content of a C-file usually depends upon when the person naturalized, under what provisions of law they applied, and whether or not there was any further activity in their case after naturalization.  Many naturalization cases re-opened later in connection with applications for replacement (of lost) certificates, derivative citizenship claims, requests for proof of citizenship in relation to job applications, background investigations, insurance claims, or pension benefits.

C-Files also include several certificate series not duplicated in court records, such as derivative citizenship certificates (A series, AA series), and certain repatriation and resumption of citizenship files (see table below).

Index Search Issues

The most common problem in searching for C-Files is identifying one person among many of the same name and approximate date of birth.  The most helpful information is:

1.  The place of residence when naturalized.  Unless searching for the naturalization of a soldier or woman who lost citizenship by marriage prior to 1922, this information is of immense value.  Provide all places where the immigrant lived (or may have lived).

2.  When trying to identify one immigrant among many with the same name, helpful information includes a street address, place of birth, names of spouse and/or children, occupation, arrival information, etc.  When up to three index references match the requested immigrant exactly, reference to the actual records can help identify the correct file.  The naturalization petition will show their street address and place (town) of birth, name the spouse or children (if any), or show the occupation.  Any of these facts or characteristic may help to distinguish one from another.

Record Request Issues

Some C-File microfilm was poorly produced a half-century ago and has deteriorated since.  In those cases record images are often faded.  We aim to provide the best possible record copy, especially in these cases.

The Genealogy Program may experience problems if researchers try to submit Record Requests without a prior Index Search Request and with the wrong C-number.  Some researchers confuse the naturalization court’s petition number with a C-number.  Others misunderstand annotations found on ship passenger lists or other documents and think they are C-numbers (or A-numbers).  If these numbers relate to a file where the name is not the name provided in the request, no file will be returned and there is no refund.

C-Files may include documents containing personal information about other persons (called "third parties") who may still be living.  This occurs in C-Files if/when the petition lists the minor children of the immigrant.  A document containing third party personal information is not releasable outside the Freedom of Information (FOIA) process, so some records received from the Genealogy Program may have some information redacted.

Where do I find a C-File number?

Standard Certificate Files numbers can be found on original naturalization certificates or may be available from court naturalization indices since September 27, 1906.  C-File numbers can always be learned by submitting a Genealogy Index Search Request on form G-1041.