How IP Leasing Works: A Practical Guide for Network Operators

IP leasing is a contract under which the registered holder of an address block (the lessor) lets another network (the lessee) use it for a monthly or yearly fee, while the block stays registered to the lessor. The lessor records the lessee in the registry database and signs a ROA so the lessee's ASN can announce the prefix in BGP. Leases on the IPXO marketplace averaged $0.35 per IPv4 address per month over the six months to September 2026, against about $23.50 per address to buy a /24-sized block in August 2026 (according to broker IPv4.Global, monthly averages).

What is IP Address Leasing?

IP address leasing is an arrangement where one organization (the lessor) grants another organization (the lessee) the right to use IP addresses for a specified period in exchange for recurring payments. Unlike purchasing IP addresses outright, leasing provides temporary access to IP resources without moving the registration.

• The lessor stays the registered holder of the block in the RIR database
• The lessee gains usage rights for a defined term
• Monthly or annual payments cover the lease period
• Addresses must be returned when the lease expires

Why IP Leasing Exists

IANA handed out its last five /8s on 3 February 2011 (NRO). ARIN ran out in September 2015, the RIPE NCC in November 2019 and LACNIC in August 2020, and all three now work from waiting lists: the RIPE NCC list gives a new LIR exactly one /24, ever, and on 25 September 2026 it held 791 LIRs with the first waiting 485 days (RIPE NCC waiting list). APNIC rations a /23 per member and AFRINIC still hands out /24 to /22 blocks under its exhaustion Phase 2. Anyone else buys on the transfer market or leases; the background is in IPv4 exhaustion.

Buying is a capital outlay (about $6,000 for a /24 at August 2026 prices), leasing is a monthly line, and many needs are temporary: a project, a migration, a seasonal peak. IPv6 does not remove the demand yet. Google's IPv6 measurements passed 50% on some days from 28 March 2026, and the weekly average was about 47% in September 2026 (Google IPv6 statistics), so IPv4-only endpoints keep IPv4 in every dual-stack plan.

Types of IP Address Leasing

IPv4 Leasing

IPv4 leases dominate the IP leasing market due to address scarcity. Organizations lease IPv4 blocks ranging from small allocations (/24 with 256 addresses) to large blocks (/16 with 65,536 addresses).

Common IPv4 lease scenarios:

• Web hosting companies serving customers requiring dedicated IPs
• Data centers expanding capacity for new clients
• Content Delivery Networks (CDNs) establishing regional points of presence
• ISPs providing temporary capacity during peak demand
• Organizations testing new services before committing to purchases

IPv6 Leasing

Despite IPv6's abundant address space, leasing remains relevant in specific scenarios:

Leased IPv6 use cases:

• ISPs offering IPv6 services without RIR membership
• Organizations testing IPv6 deployment before requesting allocations
• Temporary projects requiring IPv6 connectivity
• Networks that need IPv6 announced from their own ASN without joining an RIR (a leased block is PA and returns to the lessor when the lease ends; a block that must follow you between providers is IPv6 PI)

A leased IPv6 /48 costs €40 per year from us (as of September 2026); the block is PA and returns to the lessor at the end of the lease. ISP-side details: IPv6 Leasing Benefits for ISPs.

The IP Leasing Process

Step 1: Assess Your Requirements

Before entering the leasing market, determine your specific needs:

Address Quantity: Calculate how many IP addresses you require based on:

• Current infrastructure needs
• Projected growth over the lease term
• Redundancy and failover requirements
• Development and testing environments

Block Size: Choose appropriate CIDR block sizes:

• /24 (256 addresses): small deployments, hosting providers
• /23 (512 addresses): growing organizations
• /22 (1,024 addresses): medium enterprises
• /21 (2,048 addresses): large deployments
• /20 (4,096 addresses): major infrastructure
• /19 and larger (8,192 addresses or more): ISPs, large data centers

Geographic Requirements: Consider where your addresses need to be announced:

• Regional Internet Registry (RIR) coverage area
• Specific countries or continents
• Proximity to your network infrastructure

Lease Duration: Estimate your usage timeframe:

• Short term (1 to 6 months): project work
• Medium term (6 to 24 months): testing and evaluation
• Long term (24 months and more): ongoing operations

Step 2: Find a Reputable Lessor

The IP leasing market includes various types of lessors:

LIR (Local Internet Registry) Members: Organizations holding direct allocations from RIRs:

• May offer more competitive pricing
• Direct control over address reputation
• Ability to handle routing and registration

Data Centers and Hosting Providers: Infrastructure companies leasing excess capacity:

• Often bundle IP addresses with other services
• Geographic diversity of address blocks
• Integrated network services

Evaluation criteria for lessors:

• Reputation and track record in the market
• Address block reputation (not blacklisted)
• Transparent pricing and contract terms
• Technical support availability
• RIR policy compliance
• Financial stability

Step 3: Verify Address Quality

Before finalizing any lease agreement, thoroughly verify the IP addresses:

Reputation Checks:

• Blacklist Status: Check the main DNS blocklists, for example Spamhaus and Barracuda
• Historical Usage: Research previous use to identify potential reputation issues
• Clean Record Verification: Check the range's history for abuse

Technical Validation:

• Routing Status: Verify addresses are properly announced in BGP
• RIR Registration: Confirm proper registration in RIR databases (WHOIS)
• Geolocation Data: Check that geolocation databases correctly identify address locations
• Reverse DNS: Verify proper reverse DNS configuration capability

Tools for verification:

# Blocklist check (octets reversed: 192.0.2.10)
host -t A 10.2.0.192.zen.spamhaus.org
host -t A 10.2.0.192.bl.spamcop.net

# IRR route objects for the prefix
whois -h whois.radb.net 192.0.2.0/24

# Registry record
whois 192.0.2.10

For what BGP actually carries, use a looking glass, RIPE RIS or our ASN lookup.

Step 4: Negotiate Lease Terms

Key elements to negotiate in your IP lease agreement:

Pricing Structure:

• Per-IP monthly or annual rates
• Volume discounts for larger blocks
• Payment schedules and methods
• Price adjustment clauses
• Early termination fees

Lease Duration:

• Initial term length
• Renewal options and procedures
• Automatic renewal clauses
• Notice periods for termination

Technical Terms:

• Routing announcement responsibilities
• BGP configuration support
• DNS and reverse DNS management
• IP reputation maintenance
• Technical support availability

Legal Provisions:

• Usage restrictions and acceptable use policies
• Liability limitations
• Dispute resolution mechanisms
• Compliance with RIR policies
• Insurance requirements

Step 5: Complete RIR Registration

Proper registration with the relevant RIR is required:

RIPE NCC region: the lessor, an LIR holding the allocation, registers an inetnum for the leased range in the RIPE Database with your organisation and contacts. The status is ASSIGNED PA, or SUB-ALLOCATED PA when you make your own assignments from it (ripe-826). Unregistered assignments are not valid (ripe-826 section 4.0), and ASSIGNED PA space cannot be kept once the lessor's service ends. Reverse DNS delegation is set on that object.

ARIN, APNIC, LACNIC and AFRINIC: the lessor stays the registered holder and records you as the user of the range where its registry provides for it; the policy positions are in the legal section below.

Routing authorisation. The lessor creates a ROA with your ASN as origin and the prefix length you will announce, and a route (or route6) object in its RIR's database with your ASN as origin; in the RIPE Database the route object needs the address-space maintainer, which the lessor holds, not the origin AS. Networks that enforce route origin validation drop RPKI-invalid routes: 68.6% of IPv4 prefix-origin pairs were RPKI-valid on 1 August 2026 (NIST RPKI Monitor) and APNIC Labs measured 26.92% of users behind ROV filtering on 29 July 2026 (APNIC blog). Your upstreams may also ask for an LOA from the lessor. Check the result with the RPKI checker before you announce.

Step 6: Configure Routing and Networking

Once registration is complete, configure your network to use the leased addresses:

BGP Configuration:

• Get a public ASN. In the RIPE region, a sponsored ASN costs €130 per year through us (as of September 2026) with no RIPE NCC membership, see ASN registration.
• Configure BGP sessions with upstream providers
• Announce leased IP blocks with proper origin AS
• Implement appropriate route filtering

DNS Configuration:

• Set up forward DNS records for your services
• Configure reverse DNS (PTR records)
• Coordinate with lessor for DNS delegation
• Implement DNSSEC if required

Network Integration:

• Assign addresses to servers and infrastructure
• Update firewall and security rules
• Configure load balancers and proxies
• Test connectivity and routing

Monitoring:

• Implement BGP monitoring for route propagation
• Set up blacklist monitoring services
• Monitor address reputation continuously
• Track IP utilization and efficiency

Cost Analysis: Leasing vs. Purchasing

The full comparison, by block size, is in IPv4 Leasing vs Purchasing (2026): Cost Analysis and Break-Even; the figures below are the September 2026 inputs.

Current Market Prices (2026)

IPv4 purchase prices, monthly averages per address reported by broker IPv4.Global (agreement-date prices, online and private sales mixed):

Small blocks cost more per address. Only /16 and larger bottomed in January 2026; the smaller sizes bottomed between April and June, and the broker described August as "upward momentum" with larger blocks leading.

IPv4 lease prices: leases on the IPXO marketplace averaged $0.35 per address per month over the six months to September 2026, so about $90 a month for a /24. For comparison, AWS has charged $0.005 per public IPv4 address per hour since 1 February 2024, about $3.65 a month or $43.80 a year per address, used or idle (AWS VPC pricing).

Break-Even Analysis

To determine whether leasing or purchasing makes financial sense, calculate the break-even point:

Formula:

Break-even period (months) = Purchase price per IP / Monthly lease cost per IP

Example Calculation:

Purchase about $23.50 per address (a /24, August 2026), lease $0.35 per address per month: $23.50 / $0.35 = about 67 months, or 5.6 years. A /20 at about $17.00 breaks even at 49 months, about 4 years. Both before registry fees.

General Break-Even Guidelines:

At August 2026 prices, leasing costs less for roughly the first four years (/20 and larger) to five and a half years (/24). Past that, buying costs less only if you already pay RIR membership, or hold the block as PI under a sponsoring LIR (see the registry costs below).

Hidden Costs Consideration

Registry costs on a purchase. RIPE NCC transfers are free of charge and usually complete within one or two business days (RIPE NCC transfers). A PA allocation can only be transferred to a RIPE NCC member: €1,000 to join and €1,800 per year under the RIPE NCC Charging Scheme 2026 (ripe-848), €1,894 from 2027 with one ASN included (ripe-867, adopted May 2026). For a single /24 the 2026 membership fee alone is about €0.59 per address per month, more than the lease average. An IPv4 PI assignment is the exception: an End User can receive it under a sponsoring LIR, and we sponsor such blocks at €135 per year (as of September 2026), setup on quote. ARIN charges $500 per transfer request plus a recipient transfer processing fee, $187.50 for a /24, on its 2026 fee schedule (ARIN fees); APNIC charges 20% of the annual fee for the resources moved (APNIC fee schedule). Capital tied up in the block and its market value are the other side of the ledger.

Leasing Additional Costs:

• Setup fees (some lessors charge initial fees)
• Early termination penalties
• Price adjustment clauses
• Technical support fees
• Address replacement costs if reputation degrades

Cash Flow Considerations

Leasing changes the cash flow:

Lower Upfront Investment:

• A /22 (1,024 addresses) costs about $24,000 to buy at August 2026 prices and about $360 a month to lease at the IPXO average.

Operational Expense vs. Capital Expense:

• Leasing payments are operational expenses, often easier to budget
• Purchases require capital expenditure approval, often more difficult
• Leasing preserves capital for core business investments

Scalability:

• Easy to scale up or down based on actual needs
• No sunk costs if requirements decrease
• Can test market demand before committing to purchases

Legal Considerations in IP Leasing

The clause-by-clause view is in Legal Aspects of IP Leasing Agreements.

Essential Contract Components

Every IP lease agreement should clearly define:

Parties and Addresses:

• Complete legal names and addresses of lessor and lessee
• Specific IP address blocks covered by the agreement
• CIDR notation and exact address ranges

Lease Term and Renewal:

• Start and end dates of the lease period
• Automatic renewal clauses and opt-out procedures
• Notice periods required for termination or non-renewal
• Conditions under which either party may terminate early

Payment Terms:

• Per-IP pricing or total lease cost
• Payment schedule (monthly, quarterly, annually)
• Accepted payment methods
• Late payment penalties and grace periods
• Price adjustment mechanisms (fixed, inflation-indexed, market-based)
• VAT and withholding: see Tax Implications of IP Resource Leasing

Usage Rights and Restrictions:

• Permitted uses of the IP addresses
• Prohibited activities (spam, malware distribution, illegal content)
• Geographic usage limitations
• Sublease prohibitions or permissions
• Transfer restrictions

Responsibilities and Obligations:

• Lessor's obligations:
  • Maintain proper RIR registration
  • Keep addresses off blocklists
  • Provide routing support
  • Handle RIR communications
• Lessee's obligations:
  • Use addresses responsibly
  • Maintain good reputation
  • Pay fees promptly
  • Comply with RIR policies
  • Return addresses upon termination

RIR Policy Compliance

None of the RIPE, ARIN and APNIC policy manuals uses the word lease. What each registry does say:

RIPE NCC: no leasing clause; the leased range must be registered as an assignment in the RIPE Database (ripe-826 section 4.0). IPv4 received by transfer cannot be transferred again for 24 months (ripe-807 2.2.1), and ripe-807 2.1 also allows temporary transfers, an alternative to a lease when you want the registration in your own name for a fixed term. PI space cannot be leased on at all: "The PI assignment cannot be further sub-assigned to other organisations" (ripe-738 2.6).

ARIN: the NRPM does not mention leasing. ARIN wrote in February 2023 that leasing "can be done if the addresses have been legitimately obtained and subsequently become unused", that "address space leased without providing Internet services cannot be used for justification when requesting IPv4 addresses from the Waiting List", and that a lease "does not grant permanent registration rights for the addresses to the lessee" (ARIN and IPv4 Address Leasing). Space received by transfer is "solely for the purpose of use on an operational network" (NRPM 8.5.2); a source that received IPv4 from ARIN in the previous 12 months cannot transfer it, and a source that transfers out cannot use the waitlist for 36 months (NRPM 8.3).

APNIC: "LIRs must only delegate addresses to customers who will be using those addresses in relation to network connectivity services provided by the LIR" (APNIC-127 section 3.1.3), and "if an LIR holding APNIC address space ceases to provide Internet connectivity services, all of its address space must be returned to APNIC" (section 4.2, APNIC policy). A lease without connectivity from the lessor sits outside that wording.

LACNIC and AFRINIC: we found no leasing provision to quote; read the registry's policy manual before leasing there.

Liability and Risk Management

Address key risks in your lease agreement:

Blacklisting and Reputation:

• Define who bears responsibility if addresses become blacklisted
• Specify remediation procedures (replacement addresses, delisting efforts)
• Address reputation monitoring responsibilities
• Include provisions for reputation-based early termination

Loss of the registration: if the lessor is closed or deregistered by its RIR, or transfers the block, the assignment goes with it. Require written notice, a migration period and a replacement or release clause.

Dispute Resolution:

• Specify governing law and jurisdiction
• Include arbitration or mediation clauses
• Define escalation procedures for disputes

Best Practices for IP Address Leasing

For Lessees (Organizations Leasing IP Addresses)

1. Conduct Thorough Due Diligence:

• Verify lessor's reputation and track record
• Check address history and reputation extensively
• Review sample contracts before committing
• Verify proper RIR registration of addresses

2. Start Small and Scale:

• Begin with minimum required addresses
• Monitor actual utilization before expanding
• Take advantage of leasing flexibility to right-size
• Build relationship with lessor before large commitments

3. Set Up Monitoring:

• Continuously monitor blacklist status
• Track BGP routing and announcements
• Monitor address utilization and efficiency
• Set up alerts for reputation issues

4. Maintain Excellent Reputation:

• Implement strict abuse prevention measures
• Respond rapidly to any abuse reports
• Maintain clean network operations
• Document security practices

5. Plan for Transition:

• Don't become overly dependent on leased addresses
• Maintain documentation for potential migration
• Consider a gradual move to addresses registered to you if long-term need
• Keep alternative solutions in mind

6. Negotiate Favorable Terms:

• Seek flexible termination clauses
• Negotiate volume discounts for larger blocks
• Include price caps or adjustment limits
• Get address replacement in writing

For Lessors (Organizations Providing IP Leases)

1. Maintain Clean Address Inventory:

• Regularly check address reputation across all blocks
• Remove addresses from service if blacklisted
• Implement systematic reputation monitoring
• Document address history and previous use

2. Implement Strong Vetting Procedures:

• Verify lessee identity and business legitimacy
• Assess lessee's technical capabilities
• Review intended use of addresses
• Check references from previous service providers

3. Use Standardized Agreements:

• Develop a standard lease agreement
• Include all necessary RIR compliance provisions
• Have agreements reviewed by legal counsel
• Update agreements as RIR policies evolve

4. Provide Technical Support:

• Offer assistance with BGP configuration
• Help with RIR registration procedures
• Provide routing support and troubleshooting
• Maintain responsive support channels

5. Keep RIR Records Current:

• Keep detailed records of all lease arrangements
• Update RIR databases appropriately
• Maintain proper documentation for audits
• Stay current with RIR policy changes

6. Implement Usage Monitoring:

• Monitor leased addresses for abuse
• Detect policy violations promptly
• Maintain ability to quickly revoke addresses if necessary
• Document all monitoring activities

Technical Implementation

BGP Configuration for Leased IP Addresses

Prerequisites:

• A public ASN (your own; a private or documentation number cannot be validated against a ROA)
• BGP-capable router or network equipment
• Upstream provider(s) willing to accept your announcements
• Letter of Authorization (LOA) from the lessor for the announcement (a free template: LOA generator)

Basic BGP Configuration Example (Cisco IOS):

! Configure BGP with your ASN
router bgp 64500

! Announce your leased IP block
network 192.0.2.0 mask 255.255.255.0
! the prefix must exist in the RIB, e.g. ip route 192.0.2.0 255.255.255.0 Null0

! Configure BGP neighbor
neighbor 198.51.100.1 remote-as 64501
neighbor 198.51.100.1 description Upstream-Provider

! Apply route filtering
neighbor 198.51.100.1 prefix-list ANNOUNCE out

! Define prefix list for announcements
ip prefix-list ANNOUNCE permit 192.0.2.0/24

Route Filtering Best Practices:

• Only announce leased blocks you're authorized to announce
• Implement strict prefix-list filtering
• Set appropriate BGP communities
• Configure maximum prefix limits
• Implement RPKI validation where possible

DNS Configuration

DNS for leased addresses:

Forward DNS:

; Example forward DNS records
www.example.com.     IN  A     192.0.2.10
vpn.example.com.     IN  A     192.0.2.20
ftp.example.com.     IN  A     192.0.2.30

Reverse DNS (PTR Records):

; Example reverse DNS zone (coordinated with lessor)
10.2.0.192.in-addr.arpa.  IN  PTR  www.example.com.
20.2.0.192.in-addr.arpa.  IN  PTR  vpn.example.com.
30.2.0.192.in-addr.arpa.  IN  PTR  ftp.example.com.

Reverse DNS Delegation:

• Coordinate with lessor for reverse DNS zone delegation
• Set the NS records for reverse zones
• Test reverse DNS resolution thoroughly
• Maintain accurate PTR records for all used addresses

Monitoring and Maintenance

Monitor leased IP addresses:

Reputation Monitoring:

• Use automated blacklist checking services (MXToolbox, MultiRBL)
• Monitor major DNSBLs hourly
• Set up alerts for new blacklist listings
• Maintain logs of reputation checks

Routing Monitoring:

• Use BGP looking glasses to verify route propagation
• Monitor route advertisements with RIPE RIS, RouteViews
• Set up alerts for routing anomalies
• Track BGP hijacking detection services

Utilization Tracking:

• Monitor which addresses are actively used
• Track utilization percentages
• Plan capacity based on utilization trends
• Optimize costs by right-sizing lease blocks

Common Issues and Solutions

Issue 1: Addresses Appear on Blacklists

Symptoms: Blocked connections and failed reputation checks

Causes:

• Previous misuse by prior lessees
• Spam or abuse from your infrastructure
• Collateral damage from nearby address blocks
• Overly aggressive blacklist policies

Solutions:

• Request immediate address replacement from lessor
• Follow delisting procedures for each blacklist
• Implement stronger abuse prevention measures
• Keep customer-facing services on addresses you monitor separately

Issue 2: Routing Issues and Connectivity Problems

Symptoms: Intermittent connectivity, unreachable services, routing loops

Causes:

• Improper BGP configuration
• Missing or incorrect route announcements
• Prefix filtering by upstream providers
• Letter of Authorization (LOA) issues
• Missing or wrong ROA (announcement RPKI-invalid)

Solutions:

• Verify BGP configuration with lessor
• Send the LOA to every upstream
• Check route propagation using looking glasses
• Coordinate with upstream providers on filtering policies
• Verify RIR registration is current

Issue 3: RIR Registration Problems

Symptoms: WHOIS information incorrect, registration disputes, compliance issues

Causes:

• Lessor failed to update RIR databases
• Incorrect information provided
• RIR policy non-compliance
• Documentation inadequacies

Solutions:

• Contact lessor immediately to correct registration
• Verify all required documentation is filed
• Check the applicable RIR policy
• Maintain copies of all registration correspondence

Issue 4: Contract Disputes

Symptoms: Pricing disagreements, term interpretation conflicts, service issues

Causes:

• Ambiguous contract language
• Misaligned expectations
• Service level disagreements
• Price adjustment disputes

Solutions:

• Review contract provisions carefully
• Engage in good-faith negotiation
• Utilize dispute resolution mechanisms in contract
• Seek legal counsel if necessary
• Document all communications

Issue 5: Unexpected Lease Termination

Symptoms: Notice of termination, forced return of addresses

Causes:

• Lessor's business changes
• RIR policy violations
• Non-payment or breach of terms
• Lessor loses the registration (closure, deregistration or a transfer)

Solutions:

• Maintain relationships with multiple potential lessors
• Keep migration plans updated
• Maintain adequate notice periods in contracts
• Consider moving to addresses registered to you
• Purchase critical address blocks if possible

Using Via-Registry for IP Address Leasing

We lease IPv6 from our own RIPE NCC allocations: a /48 costs €40 per year and a /44 €80 per year, larger sizes on request. The block is PA space: it is announced from your ASN, we create and maintain its ROA, and it returns to our pool when the lease ends. For an ASN you already hold, the inet6num, route6 object and ROA are created automatically after payment; the LOA is generated for you and reverse DNS is set from the dashboard. Details and order form: IPv6 leasing.

For IPv4 we take lease requests and quote after verification, from €0.50 per IP per month as of September 2026 (IPv4 leasing). An ASN is required: the block is announced from your own AS.

Frequently Asked Questions

Can I lease IP addresses without being an LIR member?

Yes. The lessor stays the registered holder, so you need no RIR membership. You do need a public ASN to announce the block; a sponsored ASN needs no membership either.

How long does it take to get leased IP addresses?

It depends on the lessor's checks and on the registry update. Our leased IPv6 blocks for an ASN you already hold are provisioned automatically after payment (inet6num, route6 object and ROA). IPv4 requests are quoted after verification.

What happens if my leased addresses get blacklisted?

Reputable lessors provide address replacement provisions if addresses become blacklisted due to previous use. However, if blacklisting results from your activities, you're typically responsible for delisting efforts. Review your lease agreement's reputation clauses carefully.

Can I sublease IP addresses I've leased?

Most lease agreements prohibit subleasing without explicit permission. Some lessors may allow subleasing under specific conditions with additional fees. Always check your contract and RIR policies before attempting to sublease addresses. PI space cannot be leased on in the RIPE region: ripe-738 forbids sub-assignment and the ripe-637 contract repeats it.

What are my obligations when returning leased addresses?

When a lease expires, you must:

• Remove all BGP announcements of the leased blocks
• Update DNS records to remove references
• Cease using the addresses in your infrastructure
• Coordinate with the lessor on RIR database updates
• Provide confirmation of de-configuration

Do the RIRs allow IP leasing?

None of the RIPE, ARIN and APNIC policy manuals uses the word lease or forbids leasing PA space, but each attaches conditions. The RIPE NCC requires the leased range to be registered as an assignment (ripe-826 4.0). ARIN excludes leased space from Waiting List justification and says the lessee gets no registration rights. APNIC ties delegations to connectivity services the LIR provides. PI space cannot be leased on. Check the registry's policy manual and your contract's governing law; the contract clauses are covered under Legal Considerations above.

Summary

Leasing IPv4 at about $0.35 per address per month beats buying for roughly the first four to five and a half years at August 2026 prices, and for longer if buying would mean paying RIPE NCC membership for a single block. What decides whether a lease works is the registration and the ROA: check both before you announce, and keep a migration plan in case the lessor loses the registration. Leased IPv6 is cheap and automatic; if the block must follow you between providers, PI is the product to look at.