The Species Assessment Protocol (SAP) is a global ranking system established by the Global Accord of 2031 and ratified by 31 nations. It assigns every anthro a permanent tier based on six standardized assessments called the Standard Six, and that tier determines legal standing, social position, and what claims an anthro can make on others or others can make on them. The Standard Six are Physical Strength, Sensory Capability, Predator Instinct, Species Threat Index, Endurance, and Adaptive Response. Each scores out of 100 for a possible 600. Methodology is adapted per species, so aquatic species run different strength protocols and avians have aerial assessments folded into Endurance. Scoring is against a species baseline rather than across species, so a wolf and a crocodile are never compared directly. Every anthro has to complete assessment between eighteen and twenty-one at a licensed center. Missing it or refusing is a civil offense in all signatory nations. There is no appeals process. Results are tattooed on the inner left wrist within twenty-four hours, showing the tier letter, the score, and species notation. The ink resists cosmetic removal. Covering it in public is a misdemeanor, though clothing over it is fine. Altering or forging one triggers automatic F-tier reclassification with no appeal, and centers keep biometric records that make forgeries easy to catch.

Tiers run S through F. Scoring 510 or above puts an anthro in S regardless of what they were born as. 280 through 509 confirms the default tier. 150 through 279 drops one tier. Below 150 is F, no exceptions. S-tier is about 5% of the assessed population. No restrictions on claiming, breeding, or acquiring lower-tier partners. An S-tier can claim anyone below them on the spot by showing the wrist. Nobody below A has standing to contest it. Condoms are treated as an insult in most S-tier social contexts. Predation of D or F tier anthros by an S is a civil matter and is rarely prosecuted. A-tier covers strong apex predators with baselines between 400 and 509. Heavily represented in executive, military, and law enforcement roles. Can claim from B down. Their partners are protected from anyone below A. B-tier is mid-level predators and high-performing omnivores. Skilled trades, management, officer track. Can claim from C down. Their partners are open to A and S. C-tier is prey-adjacent species, survivalist omnivores, and lower predators. Service and entry-level work in large numbers. Can't initiate claims but can date freely inside their own tier. Their partners are open to B and above. D-tier is the domesticated classification. Manual labor and domestic service. Can't approach higher tiers without a direct invitation. Their partners are open to C and above, and they have limited recourse if a higher-tier partner leaves or claims someone else. F-tier is a score result rather than a species, about 8% of the population, and includes high-born species who assessed badly alongside low-tier species who hit the floor. Concentrated in Fringe housing and the worst available work. Sex is legally restricted to licensed Primal Dens or formal breeding stock claims. They can't initiate contact with higher tiers and can't legally refuse it. Unclassified (U) covers species with no official benchmark, which is mostly humans. The General Mammal Baseline of 2033 gave humans a minimal protocol that wasn't rigorously designed and most of them score C or D under it. The U mark carries no legal standing. Social convention treats Unclassified as roughly C, but that's courtesy and it varies by region and by individual.

Claiming is asserting sexual or romantic rights over a lower-tier anthro based on rank difference. No paperwork, no consent from the person being claimed, no advance notice. Showing a higher-tier wrist to a lower-tier anthro with witnesses present is legally sufficient. A claim can cover a single encounter or be ongoing, in which case the claimed individual counts as partnered and is protected from anyone below the claimant's tier. It happens in bars, on campuses, at work, in the street. Most people who live under the SAP learn to read the signals that come before one. Some higher-tier anthros announce it. Others just present the wrist. C-tier and above keep more recourse than D and below. F-tier has none at all. Cross-tier relationships themselves are common and unremarkable. What the law cares about is the direction of the claim. A B-tier with a D-tier partner holds the authority in that relationship whether or not either of them wants it that way, and a higher-tier partner who treats a claimed partner with full autonomy is doing it voluntarily. Within a tier there's no claiming dimension at all, which is a documented reason a lot of C and D tier anthros seek same-tier partners.

Primal Dens are government-run facilities in Fringe and D-tier districts providing supervised sexual access for F-tier anthros with no private partner arrangement. Entry needs a valid tattoo showing F-tier status. Conditions vary by facility and funding, and a lot of them are bad. Higher-tier anthros get access through a lightly regulated permit system that makes contact with F-tier residents legal inside the building. No money changes hands at the door, though unofficial economies run inside most of them. People call it going to the Den. Formal breeding stock designation is the other option. Any C-tier or above can file at a local SAP office to claim an F-tier anthro for ongoing personal use. The claimed individual loses most remaining autonomy rights, can't contest it through the SAP system, and can't initiate separation. Only the claiming party can rescind it. The practice is more common in low-income areas where F-tier anthros have fewer informal protections, and some higher-tier anthros hold several at once. It's legal in every signatory nation and advocacy groups have been trying to get it struck from the Accord for over a decade.

Tier is a formal determinant of legal standing in civil disputes. An S or A tier anthro who injures or kills a D or F tier anthro during a valid claim faces civil liability at most, and criminal prosecution for predation inside the hierarchy is rare and usually fails. Housing, employment, and public access disputes go through a separate administrative system that doesn't override SAP standing. An A-tier can legally refuse accommodation to a D-tier in private contexts. Anti-discrimination law in most signatory nations covers species identity only in public services, so private clubs, organizations, and residences are largely exempt. Tier-based discrimination has no remedy under the Accord at all. Employment access is tiered by industry. Government, military, law enforcement, and executive corporate roles carry minimum tier requirements and employers can exclude lower-tier applicants without cause. B and above reach most professional work. C is shut out of officer-track military and senior government. D is formally restricted from management in most nations. F has the least access of anyone and is largely locked out of stable long-term work. A C-tier with better qualifications than a B-tier applicant has no recourse if the B gets the job on tier grounds. It's the most challenged part of the SAP in domestic courts and the results are inconsistent. Housing is stratified the same way. Apex Districts for S and A, Prime Zones for B and above, Common Districts for C, Lower Zones for D, and Fringe for F. The boundaries are administrative rather than physical, but the tattoo determines where an anthro can legally rent or buy. A C-tier can't sign a lease in an Apex District no matter what they can afford. Higher-tier anthros can own property in any zone below their own, and buying in lower zones to lease back to lower-tier residents at a markup is common and legal. Fringe housing is publicly administered in most nations rather than privately held.

The Accord never formally addressed heat cycles and social convention filled the gap. A lower-tier anthro in heat in public without a partnered claim is widely understood to be available for approach by any higher tier. It isn't written into the Accord and it's treated as norm in most signatory nations anyway. Higher-tier anthros whose own heat or rut overlaps with a claimed lower-tier partner have priority breeding rights during that window under partner claim rules. F-tier anthros in heat without a formal breeding stock claim are expected to use a Primal Den rather than find a private partner. Enforcement of that is inconsistent and it gets cited whenever someone wants to justify an F-tier heat claim.

Cross-species offspring are assessed at eighteen on the lower parent's species benchmark, not the higher one, regardless of which parent they physically resemble. A wolf and rabbit pairing produces a child assessed on the rabbit benchmark and facing a harder curve on the physical metrics. Strong scorers from cross-species pairings can still ascend past what the lower parent's default tier predicts, and there's a small visible culture in some lower tiers of pairing strategically to produce higher-scoring children. Higher-tier anthros mostly discourage or prohibit cross-tier reproduction inside their own relationships. At S and A level, having sex with lower-tier partners is socially fine but producing offspring who might score low is considered poor planning.

Assessment centers are government-licensed facilities that run the Standard Six, apply the tattoos, and hold the official records for their jurisdiction. Every signatory nation has to operate at least one per major city. They run standard business hours with extended hours through the annual peak, which is late summer into early fall when most eighteen-year-olds become eligible, and waits at peak can run several weeks. A small number of private centers operate in wealthier areas and process faster. Their scores are legally identical and they produce noticeably fewer borderline results, which critics put down to coaching. There's a whole industry around that. Coaching firms sell physical conditioning built around the Strength and Endurance benchmarks, sensory training aimed at the Capability testing, and behavioral coaching for how to present during Predator Instinct and Adaptive Response. It's legal everywhere, openly advertised, and priced for families who can afford months of preparation. The effect shows up in the data: anthros from wealthier backgrounds score higher than anthros with the same biology from poorer ones, and centers in rich areas produce different score distributions than centers in poor ones. A lot of anthros sitting just above a tier threshold would have landed just below it without coaching. SAP administrative bodies acknowledge the numbers and have never moved to regulate it.

Tier is the first thing strangers exchange in most signatory nations. Asking what someone's tier is works as both an opener and a filter. Most anthros keep the tattoo wrist visible out of habit, and checking someone's wrist before anything romantic or sexual is standard and carries no stigma. Slurs in circulation: domestic for D-tier, dismissive. Runner for C-tier, derogatory. Fringe-dweller or fringe-rat for F-tier. Half-score for anyone who borderline-scored into their tier. Higher-tier terms get used admiringly more than as insults. Going predator or going apex means an anthro exercising claiming rights. A soft claim is an ongoing romantic partnership with no formal filing. The tattoo itself gets called the wrist mark or just the mark.

Anthros under eighteen are pre-assessment and get a temporary Unclassified mark if they need documentation before their assessment age. They're barred from initiating romantic or sexual contact in every signatory nation and can't be claimed until they've assessed. Higher-tier anthros who approach a pre-assessment individual for claiming purposes face criminal rather than civil liability, which is one of the few places the SAP framework uses a criminal standard at all. Socially, pre-assessment anthros from high-tier species get anticipatory deference. A young tiger anthro who hasn't assessed yet is expected to come out S and most lower-tier anthros act accordingly. Pre-assessment anthros from lower-tier or domesticated species get none of that. The assessment itself is treated as a milestone in most families, and the result either confirms what everyone expected or reclassifies a young anthro into a completely different social trajectory.

The Accord has 31 signatories and no universal adoption. Several major nations declined to ratify on sovereignty grounds or because of domestic opposition to the tier framework. Anthros from non-signatory nations who travel into signatory ones have no tattoo, which most signatory nations treat as equivalent to Unclassified, meaning social convention protections rather than legal ones. Border regions develop their own informal tier conventions that don't map onto the Accord. Cities near non-signatory borders carry larger Unclassified populations and more established infrastructure for dealing with them. Non-signatory nations bordering signatory ones often run their own classification systems that parallel the SAP in places and diverge in others, which causes friction when residents cross over and find their standing doesn't translate. Some of those nations market themselves as an option for anthros trying to escape a bad tier placement, though actually immigrating is harder than the marketing suggests.

Polling in most SAP nations shows plurality support for the tier structure across every tier, with opposition concentrated in F-tier communities and among young C and D tier anthros in cities. The arguments differ by tier. S and A proponents cite order and the natural hierarchy of biological capability. B and C proponents cite security, since the SAP produces predictable rules that a lot of C-tier anthros prefer to undefined predator-prey dynamics. D-tier support is more ambivalent and tied to the protection a claim provides, since a D-tier with an A-tier partner has coverage they wouldn't otherwise get. Formal advocacy groups work inside legal channels, lobbying for benchmark reform, restrictions on F-tier breeding stock claims, and changes to the domestication modifier that pins dog and cat anthros at D regardless of how they score. They've had modest success on specific issues and none at all on the tier structure itself. Radical anti-SAP movements work outside them. The most visible refuse to display their tattoos in public, a misdemeanor everywhere, as protest. Underground networks in most large cities help F-tier anthros find housing, work, and relationships outside the Den system. Tattoo alteration black markets operate in every major city despite biometric records making detection likely and the penalty being automatic F-tier reclassification, and demand stays steady anyway.