SUM-110 – Summons—Cross-Complaint

Jurisdiction: Country: United States | Province or State: California

What is a SUM-110 – Summons—Cross-Complaint?

A SUM-110 is the court’s official summons for a cross-complaint in a California civil case. It is a court-issued notice that tells a person or entity named in your cross-complaint that you have sued them in the existing case. It explains that they must respond within a set time or risk default. It also identifies the court, the case, and the cross-complainant. You must serve it with your cross-complaint to start the court’s power over the new cross-defendant.

You use this form when your cross-complaint names anyone who is not yet a party to the case. The clerk issues it. You do not sign it. The court’s seal and the clerk’s signature make it valid. Proper service of the issued summons, along with the cross-complaint, creates the cross-defendant’s duty to respond.

Who typically uses this form?

Defendants and respondents who become cross-complainants use it. Their lawyers complete and submit it for issuance, or self-represented litigants do. Process servers then use the issued summons during service. Cross-defendants receive it. The judge uses it to confirm proper notice and jurisdiction if default or other relief is sought.

Why would you need this form?

Because a cross-complaint against a new party is not enough on its own. The court must issue a summons. Then you must serve the summons and the cross-complaint using approved methods. Without an issued and properly served summons, the court lacks personal jurisdiction over that new party. That means no enforceable default and no binding judgment against them.

Typical usage scenarios

• You are sued after a car accident. You believe a different driver or a vehicle manufacturer shares fault. You file a cross-complaint for equitable indemnity and need to bring that person or company into the case. You must serve a SUM-110 with the cross-complaint.

• A homeowner sues your construction company. You cross-complain against a subcontractor for defense and indemnity. The subcontractor is not in the case yet. You serve SUM-110 with your cross-complaint.

• A landlord sues you for property damage. You file a cross-complaint against your tenant’s guest who caused the damage. The guest is a new party. You serve SUM-110.

• A business partner sues you for breach of contract. You cross-complain against the business’s vendor for indemnity and contribution. The vendor is a new party. You serve SUM-110.

• An insurer subrogates against you. You cross-complain against another insurer or an adjuster’s employer. If that party is not already in the case, you serve SUM-110.

In short, SUM-110 is the summons tied to your cross-complaint. It is the tool that opens the door to the court for each new cross-defendant.

When Would You Use a SUM-110 – Summons—Cross-Complaint?

You use SUM-110 when your cross-complaint names a new cross-defendant who has not already appeared in the case. This includes individuals, corporations, LLCs, partnerships, associations, and public entities. If you only cross-complain against parties who have already appeared, you typically do not use SUM-110. For existing parties, service of your cross-complaint is usually made on their attorney. No new summons is required for them.

Consider these situations:

You are a defendant in a personal injury case. You believe a third driver caused the crash. You file a cross-complaint against that third driver. The third driver is not an existing party. You must have a SUM-110 issued and serve it with your cross-complaint.

You are a general contractor sued for defective work. You file a cross-complaint against your framing subcontractor. The sub is a new party. You need an issued SUM-110 and formal service.

You are a tenant sued for unpaid rent and damage. You cross-complain against your roommate for contribution. The roommate is not in the case. You need SUM-110.

You are a small business owner sued over a product. You cross-complain for indemnity against the upstream supplier. The supplier is not yet a party. You use SUM-110.

You are sued for defamation. You cross-complain against a social media account owner who helped publish the statement. If that person is not already in the case, you use SUM-110.

You are a property manager sued by an HOA. You cross-complain against a former vendor. The vendor is a new party. You use SUM-110.

Three practical checkpoints help you decide:

• Does your cross-complaint name anyone not already appearing in the case? If yes, you need SUM-110 for each such party.

• Are you filing only against the plaintiff or co-defendants who already appeared? If yes, you can usually skip SUM-110.

• Are you unsure if a party has appeared? Check the court docket or ask the clerk. When in doubt, confirm appearance status before you file and serve.

Legal Characteristics of the SUM-110 – Summons—Cross-Complaint

A SUM-110 is legally binding once the court issues it and you serve it properly with the cross-complaint. It is an official court summons. It orders the cross-defendant to respond within a fixed time. If the cross-defendant does not respond in time, you can request entry of default and seek default judgment, assuming service was valid.

Enforceability comes from three pillars:

• Issuance by the clerk. The court must issue the summons. The clerk’s signature and the court seal show the form is valid. You cannot issue or sign it yourself. Many courts issue electronic summonses. Those are valid when signed or stamped by the clerk.

• Proper service. You must serve the issued summons with the cross-complaint. Service must follow approved methods. A nonparty adult or a registered process server must serve. You then file a proof of service of summons. If service is defective, the court lacks personal jurisdiction. Default and judgment can be set aside.

• Clear identification. The summons must match the case. The case number, court location, and party names must be correct. The “Notice to the person served” section must reflect the capacity of the person or entity you served.

General legal considerations:

• Response deadline. A cross-defendant usually has 30 calendar days after service is complete to file a response. Service can be personal, substituted, on an agent, or by approved mail methods. Some methods delay the “completion” date. Track the proper deadline.

• One summons per cross-defendant is best practice. You can list several on one, but serving a tailored copy reduces confusion.

• Capacity matters. The “Notice to the person served” checkboxes identify who you served and in what capacity. There are options for individuals, corporations, LLCs, partnerships, public entities, minors, wards, conservatees, and persons sued under a fictitious name. Serving the right person in the right capacity is critical.

• New parties require formal service. Parties who have already appeared do not need a summons for your cross-complaint. Serve those parties through their counsel.

• Proof of service. File a proper proof of service of summons for each cross-defendant. The proof shows how, when, where, and to whom you served. Courts rely on it when you seek default or other orders.

• Consequences of defects. If the summons is not issued, is altered, or is not served with the cross-complaint, the court can deny default. The cross-defendant can move to quash service. Even if default is entered, judgment can be vacated for lack of proper service.

• Time and trial impact. Late service on a new cross-defendant can affect case management. The new party can ask to continue deadlines or trial. Plan service early to avoid delay.

In short, the SUM-110 is enforceable because it is a court order, issued and sealed by the clerk, and backed by service rules. Follow those rules closely to protect your claims.

How to Fill Out a SUM-110 – Summons—Cross-Complaint

Follow these steps to complete, issue, serve, and file your SUM-110.

Step 1: Confirm you need this summons

• Review your cross-complaint. Identify every cross-defendant who is not already in the case.
• For each new cross-defendant, plan to obtain a SUM-110 and serve it.
• For existing parties, plan to serve your cross-complaint on their counsel without a summons.

Step 2: Gather the details you will need

• The exact case number from the original case.
• The full court name, street address, mailing address, and branch name.
• The original case caption (plaintiff/petitioner versus defendant/respondent).
• Your name and contact information. If you have counsel, provide your attorney’s information.
• The full legal names and capacities of each cross-defendant. For entities, identify the correct legal name and, if possible, the agent for service of process.

Step 3: Complete the top section (attorney or party information)

• In the space for “Attorney or Party Without Attorney,” enter your name, mailing address, phone, and email.
• If you are self-represented, indicate that you are self-represented.
• If you have a lawyer, list the lawyer’s name, firm, address, phone, email, and bar number.

Step 4: Enter the court information

• Identify the court as the Superior Court of California, County of [County Name].
• Enter the court’s street and mailing address and the branch name. Use the same location as the original case.

Step 5: Enter the case caption and number

• Copy the case number exactly as it appears in the original case.
• Keep the same plaintiff/petitioner and defendant/respondent names and ordering as the main case caption. Do not swap roles.
• Your cross-complaint creates you as a cross-complainant, but the main caption remains the same.

Step 6: Identify the cross-complainant and cross-defendants

• Where the form asks for the cross-complainant’s attorney or party, enter your information again, if prompted.
• In the “To the Cross-Defendant” area, list each cross-defendant by full legal name. Use exact names for individuals and registered names for entities.
• If you need more space, use an attachment labeled “Additional Cross-Defendants” and check any box on the form that refers to an attachment.

Step 7: Do not alter the notice language

• The form contains preprinted notices about deadlines and defaults. Do not change that language. Courts rely on the standard text.

Step 8: Handle the “Notice to the Person Served” section

• This section identifies the capacity in which the person was served.
• If serving an individual in their own capacity, check “as an individual.”
• If the cross-defendant uses a fictitious business name, and you served the person under that name, check “as the person sued under a fictitious name.”
• If you served an entity, check “on behalf of” and choose the correct type:
• Corporation
• LLC or other unincorporated association
• Partnership or limited partnership
• Public entity
• Minor (through a parent or guardian)
• Ward or conservatee (through a guardian or conservator)
• If you used substituted service on a household or business occupant, mark the appropriate option.
• If you are unsure which box applies, consult your process server. The server can complete this section at the time of service.
• Accuracy here matters. It must reflect who was actually served and in what capacity.

Step 9: Leave the date and clerk signature lines blank

• Do not fill in the date, the clerk’s name, or the deputy’s signature. The clerk will complete these when issuing the summons.
• You also do not place the court seal. The clerk does.

Step 10: Submit the summons for issuance

• File your cross-complaint. At the same time, submit the completed SUM-110 for issuance.
• You can file in person or electronically, depending on the court. If you file in person, bring the original and copies. If you e-file, upload as instructed.
• Wait to receive the issued summons. It will bear the clerk’s signature and the court’s seal. Keep extra copies for service.

Step 11: Prepare service packets

• For each cross-defendant, prepare a packet that includes:
• A copy of the issued SUM-110 naming that cross-defendant.
• A filed or conformed copy of your cross-complaint and all attachments and exhibits.
• If you listed multiple cross-defendants on one summons, prepare a separate packet for each person. Use a copy of the same issued summons and highlight or mark the name for clarity.

Step 12: Choose a proper method of service

• Use a process server or another adult who is not a party.
• For individuals in California, personal service is best. Substituted service at a home or business is allowed with follow-up mailing. Service is complete after a short delay if substituted.
• For corporations and LLCs, serve the registered agent or an authorized officer. Verify the current agent from public records.
• For partnerships, serve a general partner or the agent.
• For public entities, serve the clerk, secretary, or other authorized officer.
• For minors or conservatees, serve the appropriate responsible adult as required. When in doubt, use personal service on the adult with authority, and deliver a copy to the minor if appropriate.
• For out-of-state parties, you can use personal service or approved mail methods that require signed receipt, depending on circumstances.
• For service by publication, get a court order first.

Step 13: Complete the “Notice to the person served” at service

• Ensure the server marks the correct checkbox on the summons to reflect the capacity served.
• The server should write in any required details, such as the name and role of the person served on behalf of an entity.

Step 14: File your proof of service of summons

• After service, have your server complete a proof of service of summons. It must detail the date, time, place, method, and person served.
• File that proof with the court. Do this for each cross-defendant.

Step 15: Calendar the response deadline

• Track the 30-day response deadline after service is complete.
• Substituted service and mail-based methods can add a few days because service is deemed complete later. Confirm the correct deadline for your method of service.

Step 16: Follow up and enforce if needed

• If the cross-defendant appears, serve all future papers on their attorney.
• If the cross-defendant does not respond by the deadline, consider requesting entry of default. Confirm that your proof of service of summons is on file and correct before you do so.

Practical tips and common mistakes to avoid:

• Use exact names. For entities, include “Inc.,” “LLC,” or “LP” if applicable. Accuracy is key to valid service and enforcement.

• Do not alter the issued summons. Once the clerk signs and seals it, do not change it. If you need to correct something material, request a new issuance.

• Do not skip the “Notice to the person served.” Courts rely on that section to confirm capacity and method of service. An unchecked or incorrect box can derail default.

• Serve early. New cross-defendants may need time to appear and participate. Late service can complicate scheduling.

• Match the case classification. Your summons must reflect the existing case. Do not try to change limited vs. unlimited through the summons. If reclassification is needed, use proper procedures.

• Keep organized records. Keep a master list of each cross-defendant, the service method, the service date, and the calculated response deadline. File proofs promptly.

• Use one summons per person when possible. It reduces confusion and simplifies proof of service.

• Coordinate with your server. Share who the target is, where to find them, and which capacity applies. Provide copies of the cross-complaint and the issued summons.

• If a cross-defendant retains counsel before service, ask counsel to accept service. If they agree, get written acknowledgment. You still file proof of service.

By following these steps, you will complete, issue, and serve SUM-110 correctly. You will give each new cross-defendant clear notice and start their response clock. That protects your cross-claims and avoids service challenges that waste time and resources.

Legal Terms You Might Encounter

• A cross-complaint is a lawsuit filed by a defendant against someone else in the same case. On this form, it means you are the cross-complainant starting a claim against one or more cross-defendants. The SUM-110 summons formally notifies those cross-defendants that a cross-complaint now exists.
• A cross-complainant is the party filing the cross-complaint. If you are completing SUM-110, you are the cross-complainant. Your name must appear exactly as it appears in the case caption and in your cross-complaint.
• A cross-defendant is the party you are suing in the cross-complaint. SUM-110 is directed to each cross-defendant you name. List each cross-defendant’s exact legal name on the form to avoid service and enforcement issues.
• A summons is the official notice from the court that a lawsuit or cross-complaint has been filed. SUM-110 tells the cross-defendant that they must respond within the stated time. The clerk issues and seals the summons after you file it.
• Service of process is the formal delivery of court papers to a party. For SUM-110, you must arrange service on every cross-defendant. Proper service starts the response deadline and gives the court authority over that party.
• Personal service means hand-delivering the summons and cross-complaint to the cross-defendant. It is the standard method to begin a case against a person or business. If personal service is not feasible, other methods may be available, but follow the rules closely.
• Substituted service allows delivery to someone else or by specific alternative means when personal service fails despite reasonable efforts. If you use substituted service, note any extra steps required to complete service, such as mailing copies and waiting periods.
• Proof of service is the form your server completes to confirm how and when they served the documents. Without proof of service filed, the court may question whether the cross-defendant received notice. Keep a copy and file the original proof with the court.
• Caption means the case heading on your documents. It includes the court, case number, parties’ names, and limited/unlimited case designation. The caption on SUM-110 must match the case exactly. Any mismatch can cause confusion or rejection.
• Limited versus unlimited civil case identifies the case type based on the amount demanded and relief sought. This selection appears in the caption. Use the same designation your case already has. Changing it on the summons will cause errors in processing.
• Issuance is the act of the court clerk reviewing, signing, and sealing SUM-110. You cannot serve the summons until it is issued. Present a completed form with the cross-complaint so the clerk can issue it and return conformed copies.
• Agent for service of process is the person or company designated by a business to receive legal papers. If you are serving a corporation, LLC, or other entity, the agent is often the proper recipient. List the entity’s full legal name on SUM-110 and serve its agent.

FAQs

Do you need a separate SUM-110 for each cross-defendant?

Yes. Prepare one summons per cross-defendant named in your cross-complaint. Each summons should list that cross-defendant’s exact legal name. You will serve each one with a copy of the cross-complaint and any required attachments.

Do you file SUM-110 before or after serving the cross-defendant?

You file it first. The clerk must issue and seal the summons before service. Only an issued summons can be served. Ask for conformed copies to serve and to keep for your records.

Do you serve the original plaintiff too?

Only if the plaintiff is named as a cross-defendant. If your cross-complaint asserts claims against the plaintiff, you must serve them. If your cross-complaint is only against new parties, serve those new cross-defendants.

Do you include the cross-complaint with the summons?

Yes. The service packet should include the issued SUM-110, the filed cross-complaint, and any attachments or court notices required in your court. If a case management order or ADR information is required in your venue, include it as well.

Do you need a registered process server to serve SUM-110?

Not necessarily. An adult who is not a party can typically serve. A registered process server is often faster and knows the rules, which reduces mistakes. For service on businesses or hard-to-serve parties, a professional can help avoid delays.

Do you have to use personal service?

Personal service is the standard for starting claims against a party. If personal service cannot be completed despite reasonable attempts, you may be able to use substituted service or other permitted methods. Follow the service rules and keep detailed notes of attempts.

Do you need to serve a business through its agent?

Usually. For corporations and LLCs, serve the agent for service of process or another authorized person. Check the entity’s official records to confirm the agent’s name and address. Address the documents to the entity’s legal name and serve the agent.

Do you need a new SUM-110 if you amend the cross-complaint?

It depends. If you add new cross-defendants, you need a new summons for each new party. If you only change your claims against already served cross-defendants, you may not need a new summons. Serve the amended cross-complaint as required and file proof of service.

Checklist: Before, During, and After the SUM-110 – Summons—Cross-Complaint

Before signing and filing

• Confirm the case number and court address match the existing case.
• Verify whether the case is limited or unlimited and mirror that on the summons.
• List the cross-complainant’s name exactly as it appears in the case.
• Gather each cross-defendant’s exact legal name. Include suffixes and “DBA” if applicable.
• Identify the correct agent for service for each business entity.
• Prepare the cross-complaint and any required attachments for filing.
• Plan your service strategy, including personal service attempts and fallback methods.
• Budget for filing and service fees, or prepare a fee waiver if needed.
• Make at least two extra copies of everything for your records.
• Prepare a service log to track attempts, dates, addresses, and server details.

During completion and review

• Check the caption for the correct court, branch, and case number.
• Ensure the party names are consistent across the summons and cross-complaint.
• Confirm the limited or unlimited designation matches the case.
• List only one cross-defendant per summons form.
• Review any language on response deadlines for clarity. Do not alter it.
• Leave the clerk’s issuance area blank. The clerk completes that part.
• Sign where required if the form calls for your signature or information.
• Proofread names, addresses, and spelling. Small errors cause big delays.
• Assemble the filing packet: SUM-110, cross-complaint, and attachments.
• Bring conformed copy requests (extra copies) for clerk stamping.

After clerk issuance

• Verify the clerk’s signature and the court seal on each SUM-110.
• Label and separate service packets by cross-defendant.
• Include the issued SUM-110, filed cross-complaint, and required notices.
• Select a nonparty adult or a registered process server to serve.
• Schedule prompt personal service at likely locations and times.
• Document each attempt. Note dates, times, addresses, and outcomes.
• If using substituted service, complete any extra mailing steps required.
• Obtain a completed Proof of Service of Summons from your server.
• File the proof of service with the court and keep a stamped copy.
• Calendar each cross-defendant’s response deadline as stated on the summons.
• Monitor for responsive pleadings and be ready to proceed.
• Maintain an organized file with all conformed copies and proofs.

 Common Mistakes to Avoid

Don’t list the wrong party name.

• Consequence: Service may be invalid. You might need to amend and re-serve, causing delay and extra costs.

Don’t serve an unissued summons.

• Consequence: The court may disregard service. You will have to re-serve with a properly issued summons.

Don’t mismatch the case caption.

• Consequence: The clerk can reject your filing. Mislabeling can also create confusion about which case the papers belong to.

Don’t skip proof of service filing.

• Consequence: The court will not see that service occurred. Deadlines and hearings may stall until proof is filed.

Don’t assume service on a business is the same as a person.

• Consequence: Serving the wrong individual can invalidate service. Always identify the authorized agent or person for the entity.

Don’t ignore the stated response deadline.

• Consequence: You could miss opportunities to manage the case timeline. Track each cross-defendant’s deadline from the date of service.

Don’t alter court-issued language on the summons.

• Consequence: Unauthorized edits can lead to rejection or challenges to service. Use the form as provided and complete only your parts.

What to Do After Filling Out the Form

File and obtain issuance

• File the completed SUM-110 with your cross-complaint. Ask the clerk to issue the summons. Request conformed copies for each cross-defendant and for your records. Verify the clerk’s seal and signature are present on every copy you plan to serve.

Assemble service packets

• For each cross-defendant, prepare a packet that includes the issued SUM-110, the filed cross-complaint, and any required local notices. Double-check the names and addresses on the envelope or cover sheet, especially for business entities and agents.

Serve each cross-defendant

• Arrange prompt personal service wherever practical. For individuals, use a home or work address where service is allowed. For businesses, serve the registered agent or an authorized representative. If personal service is not possible after diligent attempts, consider permitted alternatives and follow any added steps.

Document and file proof

• Obtain a signed Proof of Service of Summons that states who was served, how, where, and when. File the completed proof with the court. Keep a conformed copy in your file. Without filed proof, the court may not recognize that service occurred.

Track deadlines and responses

• Calendar the response deadline shown on the summons for each cross-defendant. Note the service date and method because these can affect timing. Watch for answers, motions, or other responses. Organize all incoming papers and update your case file.

Handle amendments or new parties

• If you amend the cross-complaint to add new cross-defendants, prepare a new SUM-110 for each new party. File the amended pleading and have the new summons issued. Serve the new parties and file new proofs of service. If you only change claims against existing parties, serve the amended pleading as required and keep proof.

Manage service challenges

• If you cannot locate a cross-defendant, keep a log of attempts and addresses. Consider alternate methods allowed by the rules when personal service fails. Be prepared to show diligent efforts if a court review becomes necessary.

Keep your records tight

• Keep a master checklist for each cross-defendant. Include dates of filing, issuance, service attempts, completed service, proof filing, and response receipt. Store conformed copies of all documents in a secure, organized file.

Prepare for the next steps in the case

• As responses arrive, plan your next filings and deadlines. Be ready to attend conferences or hearings and to exchange required disclosures or case information. Continue tracking all parties’ status so the case progresses without avoidable delays.