A research desk for Indonesian equities, built for a small private circle: the market, each stock, the group's trade plans, foreign flow and who owns what, in one place. Every figure in Rupiah.
Runs on sample data: real company names, made up prices, flows and plans. Ten stocks and a few pages of the full app. Nothing you do is saved and no AI calls are made. Not investment advice. Back to michaelsutanto.com
Families are named from a roster we maintain. The shared shareholders and shared board members that IDX publishes then supply the evidence for each link — and propose the vehicles nobody listed.
4 named groups · 0 links found in the register
Where do these groups come from?
Two places. The family names and their known vehicles come from a roster we maintain by hand, because no amount of computation turns a shared shareholder into the words “Prajogo Pangestu”. Everything else — the evidence under each vehicle and the dashed additions — is computed from the shareholder registers and boards that IDX publishes for every listed company.
What does a dashed border mean?
That nobody put the vehicle on the roster. The register or the board links it to this family, so the map proposes it — but no person has checked it. A solid border means a human named it. Treat dashed as a lead, not a fact.
Why does the same company appear in two groups?
Because two families genuinely hold it. BUMI is Bakrie and Salim, MDKA is Thohir and Saratoga, EMTK is Salim and Sariaatmadja. Forcing one owner would delete the more interesting half of the truth, so it is tagged cross-held and appears in both.
What counts as a link?
Two things IDX publishes. A shared holder — the same entity on both registers — kept only where it controls one side or holds at least 5% of both, because a 6% stake in one company and 0.2% in another is a portfolio rather than a group. Or shared people: at least two board members in common, of whom two are executives. One person in common is a coincidence at this scale.
Why is a company I expected not here?
Most likely the roster does not name its family yet. The count of linked companies belonging to no named group is at the top of this page, and that is the size of the gap. Adding a family is a change to the roster, not to the code.
What is the score?
The same measure the foreign accumulation leaderboard uses, applied to a whole family: net foreign buying over the window as a share of the group's combined free float value, how many days of the group's own turnover that represents, and how consistently the sessions pushed one way. Ranking by rupiah alone would print whichever family owns a bank at the top every day.
What are significant investors?
Within each family, vehicles are ordered by net foreign flow over the last 30 sessions, largest buying first. Refreshes with each flow import. · to 2026-10-23
Petrochemical-to-renewables complex. The single biggest driver of IHSG index weight moves in 2023-2025; watch for cross-holding cascades between BRPT/TPIA/BREN.
Solid border = named on the roster. Dashed = inferred from a shared holder or director. Dotted = reported but unconfirmed, and excluded from the combined market cap.
Select a vehicle to see why it is in this group
No links found inside this group yet.
Tobacco fortune reinvested into banking and telecom towers. BBCA is the largest listed holding on the exchange by market value; TOWR holds SUPR and DATA through Protelindo.
Solid border = named on the roster. Dashed = inferred from a shared holder or director. Dotted = reported but unconfirmed, and excluded from the combined market cap.
Select a vehicle to see why it is in this group
No links found inside this group yet.
Not a family. Danantara and the sector holdings - MIND ID, Pertamina, Telkom, Semen Indonesia, Pelindo, Bio Farma - are the largest owner on the exchange. Listed here because state control is precisely what decides free float, and free float is what decides index eligibility. Not exhaustive.
Solid border = named on the roster. Dashed = inferred from a shared holder or director. Dotted = reported but unconfirmed, and excluded from the combined market cap.
Select a vehicle to see why it is in this group
No links found inside this group yet.
Indonesia's broadest conglomerate: food staples, plantations, telco infra, data centres, energy and banking. Cross-holds BUMI with Bakrie, FAST with Jhonlin and EMTK with the Sariaatmadja family.
Solid border = named on the roster. Dashed = inferred from a shared holder or director. Dotted = reported but unconfirmed, and excluded from the combined market cap.
Select a vehicle to see why it is in this group
No links found inside this group yet.
Names on three or more registers that are not a family, and — in the section below them — directors and commissioners on three or more boards. Some are broker nominees holding for unrelated clients; some are individuals who own pieces of several unrelated businesses; some are professional board members whose seats say nothing about ownership. All are listed rather than linked, because joining their companies to each other would invent a conglomerate that does not exist.
What this map is not
Evidence of affiliation, not proof of coordination. Professional directors sit on unrelated boards, two people can share a common name, and a nominee company may serve unrelated clients. Every link shows its reason so you can dismiss a bad one — read them before acting on a cluster.