NLP Lineage

9 July 2026 · Reasoning

GPT-5.6 Sol

GPT-5.6 Sol

OpenAI

Date
9 July 2026
What the date marks
Model release
Kind
Model
Organisation
OpenAI
Access
API only
Other dates
preview 2026-06-26
Threads
In the guided tour
Chapter 14. Where the threads meet now
Learning phases
3. API usage and prompting

Too recent for its influence to be judged: no later milestone in the data descends from it yet. How levels are decided

Figures quoted here are reported by the organisation that built it, not independently verified.

Read the primary source (openai.com)

Full summary in progress. Until then, this page shows the milestone's record from the research data.

What it changed

Before it

The GPT-5 series had run through five point releases.

The problem

Different workloads want different capability and cost profiles.

What it introduced

A named tiered family, previewed to selected partners before general release.

Why it matters

Shows staged, partner-first release becoming normal at the frontier.

What modern models inherit

Named capability tiers within a generation.

What came next

Continued 5.x iteration.

Before and after

The milestones it descends from, and the milestones that descend from it. Work developed alongside it is not counted. Weak links are left out unless you include them.

Before: where it came from

GPT-5.6 Sol has 49 documented ancestors across 11 chapters, reaching back to Recurrent networks in 1990. Showing its direct parents and the 18 turning points among them.

GPT-5.6 Sol has 49 documented ancestors across 11 chapters, reaching back to Recurrent networks in 1990. Showing all of them.

GPT-5.6 Sol has 69 recorded ancestors, including indirect ones, across 11 chapters, reaching back to Recurrent networks in 1990. Showing its direct parents and the 18 turning points among them.

GPT-5.6 Sol has 69 recorded ancestors, including indirect ones, across 11 chapters, reaching back to Recurrent networks in 1990. Showing all of them.

  1. 2026GPT-5.6 SolThis milestone.
  2. 2026GPT-5.5GPT-5.6 Sol built directly on thisChapter 14. Where the threads meet now
  3. 2026GPT-5.4GPT-5.5 built directly on thisChapter 14. Where the threads meet now
  4. 2026GPT-5.3-CodexGPT-5.4 built directly on thisChapter 13. Models that act
  5. 2025GPT-5.2GPT-5.3-Codex built directly on thisChapter 14. Where the threads meet now
  6. 2025GPT-5.1GPT-5.2 built directly on thisChapter 14. Where the threads meet now
  7. 2025GPT-5GPT-5.1 built directly on thisChapter 14. Where the threads meet now
  8. 2025o3 releasedGPT-5 built directly on thisChapter 12. Thinking longer
  9. 2024o3 announcedo3 released succeeded thisChapter 12. Thinking longer
  10. 2024o1 Turning pointo3 released built directly on thisChapter 12. Thinking longer
  11. 2024GPT-4oGPT-5 succeeded thisChapter 11. Seeing and hearing
  12. 2023GPT-4VGPT-4o built directly on thisChapter 11. Seeing and hearing
  13. 2023Function callingo3 released was influenced by thisChapter 13. Models that act
  14. 2023GPT-4 Turning pointGPT-4o built directly on thisChapter 7. The assistant goes public
  15. 2022GPT-3.5 Turning pointGPT-4 succeeded thisChapter 7. The assistant goes public
  16. 2022InstructGPT Turning pointGPT-4 built directly on thisChapter 6. Teaching models what people want
  17. 2022Chain of thought Turning pointo1 was influenced by thisChapter 12. Thinking longer
  18. 2021FLANInstructGPT was influenced by thisChapter 6. Teaching models what people want
  19. 2020RLHF for summarisation Turning pointInstructGPT built directly on thisChapter 6. Teaching models what people want
  20. 2020GPT-3 Turning pointChain of thought was influenced by this
    InstructGPT built directly on this
    GPT-3.5 built directly on this    Chapter 5. Scale becomes a science
  21. 2020Scaling laws Turning pointGPT-4 built directly on thisChapter 5. Scale becomes a science
  22. 2019T5 Turning pointFLAN was influenced by thisChapter 4. Pretrain once, use everywhere
  23. 2019C4 Turning pointT5 was influenced by thisChapter 4. Pretrain once, use everywhere
  24. 2019RLHF for LMsRLHF for summarisation built directly on thisChapter 6. Teaching models what people want
  25. 2019Sparse Transformer Turning pointGPT-3 built directly on thisChapter 4. Pretrain once, use everywhere
  26. 2019GPT-2 Turning pointScaling laws was influenced by thisChapter 4. Pretrain once, use everywhere
  27. 2019WebTextGPT-2 was influenced by thisChapter 4. Pretrain once, use everywhere
  28. 2018BERT Turning pointT5 was influenced by thisChapter 4. Pretrain once, use everywhere
  29. 2018SentencePieceT5 built directly on thisChapter 4. Pretrain once, use everywhere
  30. 2018GPT-1GPT-2 built directly on thisChapter 4. Pretrain once, use everywhere
  31. 2018ELMoBERT was influenced by thisChapter 4. Pretrain once, use everywhere
  32. 2018ULMFiTBERT was influenced by thisChapter 4. Pretrain once, use everywhere
  33. 2017CoVeELMo was influenced by thisChapter 3. Attention, then only attention
  34. 2017Transformer Turning pointScaling laws built directly on thisChapter 3. Attention, then only attention
  35. 2017RLHF originRLHF for summarisation built directly on thisChapter 6. Teaching models what people want
  36. 2016Layer normTransformer built directly on this
    GPT-2 built directly on this    Chapter 3. Attention, then only attention
  37. 2015Residual connectionsTransformer was influenced by thisChapter 3. Attention, then only attention
  38. 2015LM pretraining Turning pointGPT-1 was influenced by thisChapter 2. Words become vectors
  39. 2015BPE tokenizationGPT-2 built directly on thisChapter 2. Words become vectors
  40. 2015Luong attentionTransformer was influenced by thisChapter 3. Attention, then only attention
  41. 2014AdamTransformer was influenced by thisChapter 2. Words become vectors
  42. 2014GloVeELMo built directly on thisChapter 2. Words become vectors
  43. 2014Seq2seq Turning pointTransformer built directly on thisChapter 2. Words become vectors
  44. 2014Attention Turning pointTransformer built directly on thisChapter 3. Attention, then only attention
  45. 2014GRU / encoder-decoderAttention built directly on thisChapter 2. Words become vectors
  46. 2013word2vecELMo was influenced by thisChapter 2. Words become vectors
  47. 2011NLP from scratchELMo was influenced by thisChapter 1. Language as probability
  48. 2003Neural LMNLP from scratch was influenced by this
    word2vec was influenced by this    Chapter 1. Language as probability
  49. 1997LSTM Turning pointSeq2seq built directly on thisChapter 1. Language as probability
  50. 1990Recurrent networksLSTM was influenced by thisChapter 1. Language as probability
  1. 2026GPT-5.6 SolThis milestone.
  2. 2026GPT-5.5GPT-5.6 Sol built directly on thisChapter 14. Where the threads meet now
  3. 2026GPT-5.4GPT-5.5 built directly on thisChapter 14. Where the threads meet now
  4. 2026GPT-5.3-CodexGPT-5.4 built directly on thisChapter 13. Models that act
  5. 2025GPT-5.2GPT-5.3-Codex built directly on thisChapter 14. Where the threads meet now
  6. 2025GPT-5.1GPT-5.2 built directly on thisChapter 14. Where the threads meet now
  7. 2025GPT-5GPT-5.1 built directly on thisChapter 14. Where the threads meet now
  8. 2025o3 releasedGPT-5 built directly on thisChapter 12. Thinking longer
  9. 2024o3 announcedo3 released succeeded thisChapter 12. Thinking longer
  10. 2024Computer useGPT-5.3-Codex was influenced by this (indirect influence)Chapter 13. Models that act
  11. 2024o1 Turning pointo3 released built directly on thisChapter 12. Thinking longer
  12. 2024Test-time computeo3 announced was influenced by this (indirect influence)Chapter 12. Thinking longer
  13. 2024Claude 3.5 SonnetComputer use built directly on thisChapter 14. Where the threads meet now
  14. 2024GPT-4oGPT-5 succeeded thisChapter 11. Seeing and hearing
  15. 2024Claude 3Claude 3.5 Sonnet built directly on thisChapter 14. Where the threads meet now
  16. 2023GPT-4VComputer use was influenced by thisChapter 11. Seeing and hearing
  17. 2023Function callingComputer use was influenced by this (indirect influence)Chapter 13. Models that act
  18. 2023Process supervisiono1 was influenced by this (indirect influence)Chapter 12. Thinking longer
  19. 2023Tree of thoughtsTest-time compute was influenced by this (indirect influence)Chapter 12. Thinking longer
  20. 2023GPT-4 Turning pointGPT-4V built directly on thisChapter 7. The assistant goes public
  21. 2023ClaudeClaude 3 built directly on thisChapter 7. The assistant goes public
  22. 2023ToolformerFunction calling was influenced by this (indirect influence)Chapter 13. Models that act
  23. 2022Constitutional AIClaude 3 built directly on thisChapter 6. Teaching models what people want
  24. 2022GPT-3.5 Turning pointGPT-4 succeeded thisChapter 7. The assistant goes public
  25. 2022ReActFunction calling was influenced by this (indirect influence)Chapter 13. Models that act
  26. 2022WhisperGPT-4o was influenced by this (indirect influence)Chapter 11. Seeing and hearing
  27. 2022HH-RLHFConstitutional AI built directly on this
    Claude was influenced by this    Chapter 6. Teaching models what people want
  28. 2022STaRo1 was influenced by this (indirect influence)Chapter 12. Thinking longer
  29. 2022Self-consistencyTest-time compute built directly on thisChapter 12. Thinking longer
  30. 2022InstructGPT Turning pointGPT-4 built directly on thisChapter 6. Teaching models what people want
  31. 2022Chain of thought Turning pointReAct built directly on thisChapter 12. Thinking longer
  32. 2021WebGPTReAct was influenced by this
    Toolformer was influenced by this    Chapter 13. Models that act
  33. 2021HHH assistantHH-RLHF built directly on thisChapter 6. Teaching models what people want
  34. 2021FLANInstructGPT was influenced by thisChapter 6. Teaching models what people want
  35. 2021CLIPGPT-4V was influenced by this (indirect influence)Chapter 11. Seeing and hearing
  36. 2020Vision TransformerCLIP built directly on thisChapter 11. Seeing and hearing
  37. 2020RLHF for summarisation Turning pointInstructGPT built directly on this
    WebGPT built directly on this    Chapter 6. Teaching models what people want
  38. 2020GPT-3 Turning pointToolformer built directly on thisChapter 5. Scale becomes a science
  39. 2020Scaling laws Turning pointGPT-4 built directly on thisChapter 5. Scale becomes a science
  40. 2019T5 Turning pointFLAN was influenced by thisChapter 4. Pretrain once, use everywhere
  41. 2019C4 Turning pointT5 was influenced by thisChapter 4. Pretrain once, use everywhere
  42. 2019RLHF for LMsRLHF for summarisation built directly on thisChapter 6. Teaching models what people want
  43. 2019Sparse Transformer Turning pointGPT-3 built directly on thisChapter 4. Pretrain once, use everywhere
  44. 2019GPT-2 Turning pointCLIP built directly on thisChapter 4. Pretrain once, use everywhere
  45. 2019WebTextGPT-2 was influenced by thisChapter 4. Pretrain once, use everywhere
  46. 2019Transformer-XLSparse Transformer was influenced by this (indirect influence)Chapter 4. Pretrain once, use everywhere
  47. 2018BERT Turning pointVision Transformer was influenced by thisChapter 4. Pretrain once, use everywhere
  48. 2018SentencePieceT5 built directly on thisChapter 4. Pretrain once, use everywhere
  49. 2018GPT-1GPT-2 built directly on thisChapter 4. Pretrain once, use everywhere
  50. 2018ELMoBERT was influenced by this
    GPT-1 was influenced by this (indirect influence)    Chapter 4. Pretrain once, use everywhere
  51. 2018ULMFiTBERT was influenced by this
    GPT-1 was influenced by this (indirect influence)    Chapter 4. Pretrain once, use everywhere
  52. 2017CoVeELMo was influenced by thisChapter 3. Attention, then only attention
  53. 2017RLHF originConstitutional AI was influenced by thisChapter 6. Teaching models what people want
  54. 2017Transformer Turning pointGPT-2 built directly on this
    Scaling laws built directly on this
    Vision Transformer built directly on this    Chapter 3. Attention, then only attention
  55. 2017ConvS2STransformer was influenced by this (indirect influence)Chapter 3. Attention, then only attention
  56. 2016Layer normGPT-2 built directly on thisChapter 3. Attention, then only attention
  57. 2015Residual connectionsTransformer was influenced by thisChapter 3. Attention, then only attention
  58. 2015LM pretraining Turning pointBERT was influenced by this
    GPT-1 was influenced by this    Chapter 2. Words become vectors
  59. 2015BPE tokenizationGPT-2 built directly on thisChapter 2. Words become vectors
  60. 2015Luong attentionTransformer was influenced by thisChapter 3. Attention, then only attention
  61. 2014AdamTransformer was influenced by thisChapter 2. Words become vectors
  62. 2014GloVeELMo built directly on thisChapter 2. Words become vectors
  63. 2014Seq2seq Turning pointTransformer built directly on thisChapter 2. Words become vectors
  64. 2014Attention Turning pointTransformer built directly on thisChapter 3. Attention, then only attention
  65. 2014GRU / encoder-decoderAttention built directly on thisChapter 2. Words become vectors
  66. 2013word2vecELMo was influenced by thisChapter 2. Words become vectors
  67. 2011NLP from scratchELMo was influenced by thisChapter 1. Language as probability
  68. 2003Neural LMNLP from scratch was influenced by this
    word2vec was influenced by this    Chapter 1. Language as probability
  69. 1997LSTM Turning pointSeq2seq built directly on this
    ELMo built directly on this    Chapter 1. Language as probability
  70. 1990Recurrent networksLSTM was influenced by thisChapter 1. Language as probability

After: what it led to

No documented descendants are recorded for GPT-5.6 Sol without weak links.

No documented descendants are recorded for GPT-5.6 Sol without weak links.

No recorded descendants are recorded for GPT-5.6 Sol.

No recorded descendants are recorded for GPT-5.6 Sol.

Direct links and their sources

Where it came from

Built directly on

What it led to

None recorded in the sources used.