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Legacy Registration Services Agreement


The Legacy Registration Services Agreement (Legacy RSA or LRSA) is offered to those organizations and individuals in the ARIN service region who hold legacy Internet number resources not covered by any other Registration Services Agreement with ARIN. Legacy holders who sign up are guaranteed the same services provided to other organizations who have a signed RSA with ARIN. A legacy number resource is an IPv4 address or Autonomous System number that was issued by an Internet Registry (InterNIC or its predecessors) prior to ARIN's inception on 22 December 1997.

There is an annual maintenance fee associated with the Legacy RSA. The annual invoice will be sent to the designated billing Point of Contact (POC) approximately 60 days before it is due.

Note that ARIN will not reclaim unutilized address space from legacy holders who sign this RSA, nor will ARIN attempt to take away legacy resources from organizations who choose not to sign it. However, signing the Legacy RSA contractually locks in a set of rights, and thus reduces the risk of future change to a minimum.

Legacy Application Process

Step 1

Send an email to to start the request process for a Legacy Registration Services Agreement.

You will need to provide the following information (putting "Legacy RSA Application" in the subject line):

  • Organization name
  • Organization ID
  • IP address block(s) or ASNs to be covered
  • Contact information for the person submitting the request – should include name and phone number

Step 2

Once a legacy application has been submitted, the requestor will receive an automated response that will include the ARIN ticket number. ARIN's Registration Services staff will then begin the process of evaluating the application to ensure that the submitted information is accurate and up to date. ARIN staff will contact the applicant if additional information is needed to evaluate the application.

Step 3

After the evaluation is completed, ARIN's Registration Services staff will send the Legacy Applicant a copy of the Legacy RSA. The Legacy Applicant will then need to complete and submit the Legacy Registration Services Agreement (Legacy RSA). In addition to the signature and contact information for an authorized officer of the company, contact information for the appropriate billing contact must also be provided. ARIN accepts signed, but otherwise unaltered, RSAs via fax, email, or postal mail. The signed Legacy RSA is not considered valid unless returned in its entirety.

The Legacy RSA is also available at:

Step 4

Upon successful evaluation of the submitted information and receipt of the signed and completed Legacy RSA, ARIN will notify the organization or individual. This marks the end of the application process and marks the beginning of the contractual agreement.

Step 5

Two months prior to the one year anniversary of the date the Legacy RSA was signed, ARIN's Billing Department will send out an invoice for the annual legacy maintenance fee. The fee is due by the anniversary date. This billing event will reoccur annually. For additional details on the annual maintenance fee for legacy resources, please see the appropriate section of the ARIN Fee Schedule.

Frequently Asked Questions about the Legacy RSA

Note: If, after reading through the information below, you still need information about legacy space in general or the Legacy RSA, please call the Registration Services Help Desk at +1.703.227.0660 or send email to

1. You released a new Legacy RSA (3.0); how is it different from previous versions?

This is a fundamental rewrite as compared to previous versions of the Legacy RSA (LRSA), and therefore it would not be useful or efficient to go through each and every change line by line.  This version of our LRSA is a compilation of the efforts of ARIN staff, as well as comments from the community, during the consultation period that ended in November 2011.  Almost every section in the LRSA 3.0 contains clarifying language, but often these are modifications to confirm terminology changes and do not necessarily alter the meaning of the paragraph or policy.  Some of the significant changes to note are as follows:

  1. In previous versions, the execution of the LRSA and the Legacy application process were bundled together.  In LRSA 3.0, the application process is separated and is removed from the contract document.  This ARIN anticipates will be helpful in adding clarity to the agreement.
  2. Language changes were introduced to more clearly specify the core of a Legacy holder’s rights under the LRSA. For example:
    • In LRSA 2.2, Section 8, Review of Legacy [holder’s] Number Resources, which is now Section 7 in LRSA 3.0, we have clarified that ARIN does not have contractual authority to take any adverse action against a Legacy holder if they are not currently using their legacy resources.  Please note that this is not a change to policy, but rather a documented clarification of the practice of this policy. 
    • ARIN has incorporated changes to clarify and reduce the references to “termination for cause” by ARIN as one can observe by comparing LRSA 2.2 Section 14(b) with LRSA 3.0 Section 14(b). 
    • There is an increased breadth of reasons on which a Legacy holder can base a “termination for cause” as can be observed by comparing LRSA 2.2 Sections 14(c) and (d) with LRSA 3.0 Sections 14(c) and (d).
  3. With regard to the provisions concerning payments, ARIN is engaging in efforts to narrow the differences between our RSA and LRSA.  In previous LRSA versions, Legacy holders were given very attractive financial terms that did not fully cover the costs in providing services to Legacy holders.  Working toward a future convergence of the RSA and LRSA forms, more flexibility is needed in this area and therefore language has been added to ensure that ARIN may change Legacy holder fees, but with the limitation that such charges will be no greater than RSA holders for the same services.  You will observe this change in Section 5(a). 
  4. ARIN edited the dispute resolution mechanism within the LRSA, Section 15(k)(ii) to broaden the options available to Legacy holders by accommodating venues in Canada as well as Miami for disputes involving Legacy Holders from the Caribbean.

2. Does the new version automatically supersede my previously signed LRSA?

This version does not automatically supersede a previously signed LRSA; however, a Legacy holder has the option of having this updated version of the LRSA be executed in place of the previously signed LRSA.  If you wish to register Legacy Internet number resources under an Org-ID that currently has a previously signed LRSA, you will be asked to execute the LRSA 3.0 to supersede your previously signed LRSA in order to include the additional Legacy Internet number resources under that particular Org-ID.

3. Can I upgrade to this version? Why should I?

As stated above, you do have the option to upgrade to this updated version of the LRSA.  You, in consultation with your contracts and legal departments, must decide whether this updated version is one into which you would like to enter.  We have updated the provisions to provide a more robust identification of the respective rights, obligations and duties of ARIN and the Legacy Holder and certain provisions have been modified in LRSA 3.0 to provide more broad and favorable terms to Legacy Holders.  If you have any questions regarding the LRSA 3.0, ARIN staff remains ready to respond to any such inquiries to assist in your decision making process and ARIN’s Associate General Counsel to discuss with you if appropriate.

4. What is a legacy number resource and who is a legacy resource holder?

A legacy number resource is an IPv4 address or Autonomous System number that was issued by an Internet Registry (InterNIC or its predecessors) prior to the inception of ARIN on Dec. 22, 1997. These resources are not covered by a Registration Services Agreement with ARIN. A legacy resource holder is any individual or organization that was directly issued legacy number resources, not their assignees.

5. How do I know if my legacy resources are already covered under an LRSA or not?

Typically, any legacy resources that are covered under LRSA will be associated with an Organization ID ending in a -Z. This is because ARIN’s current system does not allow for multiple RSA types to be associated with a single Org ID. If you have any questions regarding your legacy resources, please contact ARIN Registration Services at the email or phone number below.

ARIN will start work this year on a resource classification project that, when completed, will allow you to specifically identify which resources are covered by either a Registration Services Agreement and/or a Legacy Registration Services Agreement as some organizations may have both.

6. How and why does this Legacy RSA differ from ARIN's standard RSA, which covers number resources previously or subsequently issued by ARIN?

ARIN is working towards narrowing the differences between the LRSA and RSA.  That being said, Legacy number resource holders will enjoy service agreement terms that differ from the terms ARIN normally requires in the RSA. The bottom line reason for these benefits is to encourage Legacy holders to regularize the legacy resources within the global IP number system under a very favorable set of terms. There are many benefits to legacy holders in doing so.

The first important benefit is the contractual promise to continue receiving Whois and IN-ADDR services. ARIN currently provides those services free to all legacy resource holders who maintain contact with ARIN. This could change if the community so desired. Correspondingly, we understand legacy holders do not expect to receive free services from the community and are willing to pay their fair share of the expenses.

The second important benefit is that the Legacy RSA precludes subsequent ARIN policies from limiting the rights of legacy resources protected under the Legacy RSA. For example, a subsequent policy that might seek to revoke underutilized resources would not apply to those who have signed the Legacy RSA.

The Legacy RSA is fundamentally intended to provide peace of mind to the legacy resource holder.

7. How long will this Legacy RSA process last?

ARIN's Board is asking all legacy resource holders to voluntarily sign the very favorable Legacy RSA as soon as possible. ARIN will make the Legacy RSA available until 31 December 2013. The global or ARIN policy process may require that more or less attractive agreements than this one will be made available in the future; however, no Legacy RSA party who signs this agreement will be forced to change to later terms. If such future policies are more favorable to legacy holders who have signed this Legacy RSA, the legacy holder has the option to sign this revised RSA. (This is included in the agreement - see Section 15(l).)

8. I have legacy IPv4 address space and want to apply for IPv6 address space as an end-user, but haven't signed the Legacy RSA. The policy seems to say that I have to have a signed RSA or LRSA in order to qualify for IPv6. Can you clarify?

There is nothing in either the IPv6 ISP policy (NRPM, or the IPv6 end-user policy (NRPM that requires legacy address holders to have a signed RSA/LRSA in order to qualify for IPv6 address space directly from ARIN. Both policies offer several different qualifying criteria for IPv6 address space and as long as an organization can meet one of them, they are eligible to receive the space.

NRPM "Direct Assignments from ARIN to end-user organizations" provides several ways to qualify for an IPv6 assignment from ARIN. The criteria that would most likely apply to your organization is to "qualify for an IPv4 assignment or allocation from ARIN under the IPv4 policy currently in effect." There is no requirement to have a signed RSA/LRSA under this criterion. An organization can qualify for IPv6, regardless of whether they have existing IPv4 space, as long as it can meet the criteria of ANY existing IPv4 policy in effect. Once an organization is approved, it must sign a standard RSA for the IPv6 address space before it can be issued.

9. If I currently hold legacy address resources, must such resources be utilized before ARIN will issue new IPv4 number resources to me?

Yes, in accordance with policy, ARIN will not issue new number resources to those that hold legacy number resources without first accounting for the utilization of those resources.

10. I have legacy resources registered in ARIN’s Whois database but have no plans to sign the LRSA. Will ARIN continue to maintain my records, and can I still make database changes to my records if I need to?

ARIN will continue to process requests from the authorized points of contact of legacy resources for updates to their registration records. Currently, there is no community driven policy specifically prohibiting ARIN from processing updates to records that are not covered under a LRSA or RSA, although that could change in the future.

11. Will updating my organization record in ARIN's database and signing the Legacy RSA require me to return to ARIN any legacy resources I hold that are not currently being utilized?

Signing the Legacy RSA will not obligate you to return unutilized resources to ARIN. The Legacy RSA explicitly states that ARIN will not reclaim unutilized legacy resources from those who sign the Legacy RSA. Additionally, it states that organizations that voluntarily choose to return unutilized legacy resources to ARIN may be eligible for a series of benefits.

12. Can ARIN take away the legacy number resources my company or institution currently holds if I don't sign a Legacy RSA?

Absent any publicly developed ARIN or global policy or a legal requirement, ARIN has no plans to "take away" the Legacy resources, even if holders don't sign a Legacy RSA. However, signing the Legacy RSA contractually locks in a set of rights, and this reduces risk of future changes in policy.

13. I have legacy resources registered in my own name and want to sign the Legacy RSA. Can I sign the Legacy RSA in my own name and not a company name, and if so, how do I proceed with this?

Yes, if your legacy resources are currently registered in the ARIN Whois database in your name, then you can sign the Legacy RSA in your name. The procedure for signing the legacy RSA begins with the completion of a legacy application which can be found on the ARIN website ( Once ARIN staff has verified the information you have supplied, they will send you a PDF copy of the Legacy RSA and instructions on how to complete the Legacy RSA.

14. I represent a US Federal Government agency and have questions about covering legacy resources under a LRSA. What do I do first?

Given that US Federal Government agencies may have unique concerns about signing a Legacy RSA or RSA, we suggest that you first contact ARIN Registration Services to discuss your circumstance. In some cases you might then be referred to ARIN’s legal counsel. You may contact the Registration Services Help Desk at +1.703.227.0660 or send email to

15. I represent a Federal, state or provisional government entity. Because of that status, I cannot agree to the LRSA provisions concerning indemnification, bankruptcy, governing law, and/or binding arbitration. How does ARIN handle this situation?

ARIN is willing to accommodate governmental entities with appropriate revisions when governmental authorities provide explanations for their concerns, as well as supporting statutory citations, if appropriate. For example, with regard to the governing law provision, if you provide ARIN with a Federal, state, or provincial statute requiring that certain law apply to the agreement, we will revise the agreement to reflect that governing law. In addition, we can substitute a non-binding mediation provision for the binding arbitration, if required by law. ARIN's attorneys can quickly respond to such issues.

16. If a legacy resource holder decides to sign the Legacy RSA, but their organization name is different from the one currently registered in the ARIN Whois database, can they still fill out the legacy application and sign the Legacy RSA?

If the organization’s name has changed due to a merger or acquisition type of activity, then the recipient organization must complete a transfer with ARIN and sign the standard RSA. Under this circumstance, they would not be allowed to sign the LRSA since they were not the original recipients of the legacy resources.

17. Why is arbitration used as a dispute resolution technique in the agreement, and how does this impact rights?

Arbitration is generally seen as more cost efficient and tailored to handle disputes about an agreement's application. Generally, reliance on courts is more formal, requires more time for adjudication, and is more expensive than arbitration, particularly where the parties mutually pick a single arbitrator. As a practical matter, to date, there have been no cases of arbitration the RSA or LRSA, so the reliance on this dispute resolution mechanism is a remote contingency.

18. I heard about the National Science Foundation General Counsel's letter about legacy address space, what does this mean?

On December 3, 2012, the National Telecommunications and Information Administration ("NTIA") formally commented on the USG's Internet protocol numbering principles, including that it recognizes ARIN as the RIR for this region. This NTIA guidance is a clear response to the issues raised by an earlier letter from National Science Foundation General Counsel (NSF GC). The NTIA's comments can be found at the following link:

Consistent with the NTIA guidance, ARIN continues its stewardship and management of both legacy and non-legacy space within the ARIN region through community-based policies.

You can read the August 30, 2012 letter from the NSF GC here.

ARIN responded to the NSF GC to clarify the issues in their letter. You can find this here.

Subsequently, NSF GC sent a letter to ARIN, found here, in which he limited his letter.

As you can see, the NSF GC was stating his letter was not an official U.S. Government legal or policy position on Internet governance.

For additional information regarding legal aspects of Internet number resources please refer to the following paper.

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