Whenever a California family law case involves minor children, the Petition or Response alone isn't enough. You also need Form FL-105, also numbered GC-120, the Declaration Under the Uniform Child Custody Jurisdiction and Enforcement Act (UCCJEA). It's a short form, but the court cannot make any custody orders without it.
Key Takeaway: FL-105/GC-120 documents where each child has lived, and with whom, so the court can confirm it has jurisdiction to decide custody. It is filed together with FL-100 (Petition) or FL-120 (Response) any time minor children are part of the case.
Form FL-105 is the California Judicial Council form titled "Declaration Under Uniform Child Custody Jurisdiction and Enforcement Act (UCCJEA)." It carries a second number, GC-120, because the same form is used in guardianship cases handled in probate court as well as family law cases.
The UCCJEA is the law that determines which state's courts have authority to make and enforce custody orders when a family's history touches more than one state. Before a California court can rule on custody, it generally needs to confirm California is the child's "home state," meaning the child has lived here for a set period immediately before the case was filed. FL-105 is how the court gathers the facts to make that determination.
Why the Court Needs This Beyond FL-100
The Petition or Response already tells the court that minor children exist and where they currently live. What it doesn't do is establish a history. The UCCJEA looks at a pattern of residence over time, not just a current address, because custody jurisdiction can otherwise be contested between two states if a family has moved recently. FL-105 supplies that pattern so the court can confirm, at the outset, that it is the right court to decide custody rather than risking a jurisdictional dispute later in the case.
FL-105 is required any time a family law case, most commonly a dissolution, legal separation, nullity, or standalone custody case, involves minor children. It is filed together with:
| Form | Filed By | When FL-105 Is Attached |
|---|---|---|
| FL-100 (Petition) | Petitioner | Whenever the Petitioner lists minor children of the marriage or partnership |
| FL-120 (Response) | Respondent | Whenever the Respondent raises custody issues, or confirms children already listed in the Petition |
If your case does not involve any minor children, you do not need to file FL-105 at all. For background on the form that most often triggers this requirement, see How to Fill Out Form FL-100.
FL-105 and GC-120 are the same form under two different numbers. Family law cases (dissolution, legal separation, nullity, and standalone custody actions) use the FL-105 number, while guardianship cases filed in probate court use GC-120.
Leaving FL-105 out of your filing when children are involved is one of the most common reasons a family law filing gets flagged as incomplete. The court cannot make custody orders without it.
Here's what the form actually asks you to provide.
1. Case Information
At the top, you'll enter the county, the names of the parties, and the case number once it's assigned, the same way you would on any other form in your case.
2. Child Information
For each minor child involved in the case, list:
- The child's full name
- The child's date of birth
If there is more than one child, you'll list each one separately; most versions of the form provide room for several children and an attachment page if you have more.
3. Residence History
This is the core of the form. For each child, you'll provide their residence history, commonly covering the last five years (or since birth, if the child is younger than five). For each address, you'll list:
- The address where the child lived
- The approximate dates the child lived there
- The name of the person or people the child lived with (a parent, both parents, a relative, or someone else)
If a child has lived in more than one state during that period, list every address in every state. This history is exactly what the court uses to apply the UCCJEA and confirm which state has jurisdiction.
4. Other Custody Proceedings
Next, you'll disclose whether you know of any other court case, past or pending, in California or any other state, involving custody or visitation of the same children. If one exists, you'll identify the court, the case number if known, and the nature of the case.
Disclosing another custody case is not optional. If two courts are unaware of each other's involvement with the same children, it can lead to conflicting custody orders and serious complications for everyone involved.
5. Other People Claiming Custody or Visitation
Finally, the form asks you to identify anyone else, beyond the parties to your case, who currently has physical custody of the children, or who claims custody or visitation rights to them. This might be a grandparent, another relative, or a guardian. If no one else fits this description, you'll indicate that as well.
6. Signature Under Penalty of Perjury
Like most Judicial Council declarations, FL-105 is signed under penalty of perjury, meaning you're certifying that everything you've written is true and correct to the best of your knowledge. Take the same care with this form that you would with the Petition or Response itself.
- Leaving the address history incomplete, especially when a child has moved between counties or states
- Forgetting to file FL-105 at all when the case involves minor children
- Not disclosing another pending or prior custody case involving the same children
- Guessing at dates instead of confirming them, since the residence history is what establishes jurisdiction
- Leaving out a relative or other adult who has actual physical custody of a child, even informally
FL-105 is filed alongside your Petition or Response and becomes part of the court file. It is generally confidential and not served on the other party in the same way as the Petition itself, since it can contain sensitive location information, though your county's Superior Court self-help center can confirm local handling.
Once filed, the court uses the residence history you provided to confirm it has jurisdiction before making any custody orders. If the history shows the children have significant connections to another state, or if another custody case is already pending elsewhere, the court may need to resolve that jurisdictional question before it can proceed. In most straightforward cases, where the children have lived in California for the required period and no other case exists, this review does not slow anything down. It simply becomes part of the record the judge relies on when custody or visitation orders are eventually requested.
Keep in mind that FL-105 establishes jurisdiction, it does not by itself decide custody or visitation. Those decisions come later, through the parenting plan, judgment, or any custody orders requested elsewhere in your case. For a broader look at how California approaches custody once jurisdiction is established, see California Child Custody Laws Explained.
Pro Tip: Gather every address, date range, and caretaker name for each child before you sit down to complete FL-105. Having this history organized in advance is the single biggest time saver on this form.
What is Form FL-105 used for?
Form FL-105, also numbered GC-120, is the Declaration Under the Uniform Child Custody Jurisdiction and Enforcement Act. It gives the court the information it needs to confirm it has jurisdiction to make custody orders, by documenting where each minor child in the case has lived, and with whom, over recent years.
Do I always need to file FL-105?
You only need to file FL-105 if your family law case involves minor children. It is filed together with form FL-100 (Petition) or FL-120 (Response) whenever children are part of the case. If there are no minor children involved, you do not file it.
How far back does the residence history on FL-105 go?
The form commonly asks for each child's residence history going back five years, or since birth if the child is younger than five. You will list each address where the child lived and the names of the people they lived with during that time.
What if my child has lived in more than one state?
You still list every address, in every state, for the requested period. This history is exactly what the UCCJEA analysis depends on, since it helps the court determine which state has jurisdiction (usually the child's "home state") to make custody decisions.
What if there is another custody case involving my children?
You must disclose it. FL-105 asks whether you know of any other pending or prior court case, in California or any other state, that involves custody or visitation of the same children. Failing to disclose another case can create serious problems, including conflicting orders from two courts.
Who else needs to be identified on FL-105 besides the parents?
The form asks you to identify anyone else who currently has physical custody of the children, or who claims custody or visitation rights to them, even if that person is not a party to your case. This might include a grandparent, other relative, or guardian.
Can I fill out FL-105 myself, or do I need an attorney?
Many people complete FL-105 themselves alongside their Petition or Response, especially when the residence history is simple and there are no other custody proceedings to disclose. A document preparation service or attorney can help if your children have lived in multiple states, or if another custody case already exists.
How Virdix Helps
The information on FL-105 has to line up with what you've already written on your Petition or Response, and gaps in the residence history are one of the more common reasons a filing gets sent back. Virdix is built to help you avoid that:
- Guided questions, walk you through each child's residence history one address at a time
- Consistency checks, so the children and dates on FL-105 match your Petition or Response
- Clear prompts, for disclosing other custody cases or other people with custody claims
- County-specific filing details, so you know how FL-105 is handled alongside your other paperwork
We don't replace an attorney for disputed custody or multi-state jurisdiction questions, but for straightforward filings, Virdix helps make sure your FL-105 is complete and consistent from the start.
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This article is for informational purposes only and does not constitute legal advice. Virdix is a document preparation service, not a law firm, and does not provide legal advice. For advice about your specific situation, consult a licensed California family law attorney.
Sources: California Courts Self-Help Center (selfhelp.courts.ca.gov), Judicial Council of California