| Inbound Relationships | Type | Active | Source | Characteristic | Refinability | Group | 
| Complement component C3d,g | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C4d | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C3 | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component 3 degradation agent (substance) | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component 4d | Is a | False | Complement component, classic pathway | Inferred relationship | Some |  | 
| Active complement enzyme of classic pathway | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C4 | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement C3 nephritic factor | Is a | False | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement C4 nephritic factor | Is a | False | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C1s | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C1 | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| C4bp complement protein | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C2b | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C1r | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Active C3b | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C1q | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C4b | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C3a | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C3g | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C3d | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C2a | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C3b | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C4a | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C3c | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C2 | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  | 
| Complement component C4c (substance) | Is a | True | Complement component, classic pathway | Inferred relationship | Some |  |